Art of Lean
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Product Development

Chief Engineer (Shusa) — Toyota's Vehicle Program Leader

Toyota's system of giving one senior engineer total accountability for an entire vehicle program — concept, quality, cost, and market success — while deliberately withholding line authority over the functional engineers who do the work. The chief engineer integrates the whole vehicle through technical depth, drawing sign-off, and persuasion rather than rank.

Quick definition: Shusa (Chief Engineer) in the TPS Encyclopedia

Japanese

主査

shusa

chief investigator; lead examiner

The Toyota chief engineer (主査, shusa) is the single engineer accountable for an entire vehicle program, from concept to launch. The records below state what the role is, where its authority comes from, how the system originated and evolved, the chief engineers' own guiding principles, the Prius as a documented test case, and how the role differs from Western program management. They are drawn from the chief engineers' own Japanese-language accounts and from Toyota's history.

The chief engineer holds total accountability for one entire vehicle program

The Toyota chief engineer system, called 主査制度 (shusa seido) inside the company, puts one veteran engineer in charge of an entire vehicle program from first concept through production launch. That engineer carries full responsibility for the product: what the car should be, who it is for, what it should cost, and how the engineering tradeoffs resolve into a coherent vehicle. The role has run continuously since the first chief engineer was named for the Crown in 1953.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The role rests on a deliberate paradox: full responsibility, limited formal authority

The chief engineer carries full responsibility for the vehicle's success or failure in the market, yet holds less direct line authority than that responsibility implies. None of the functional engineers who design the car report to the chief engineer. This is not an oversight. The tension is designed: it forces the chief engineer to lead through competence and concept clarity rather than command.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

The chief engineer leads through technical ability and persuasion, not command

Because the role has little authority to order the functional departments, the chief engineer integrates the vehicle through technical depth, direct engagement, and persuasion. The chief engineer surfaces constraints early, forces tradeoff discussions into the open, and persuades specialists through data and a clear concept. The authority comes from earned respect and technical credibility, not an org-chart position above the engineering staff.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

The chief engineer owns the full product: concept, engineering, cost, production, and sales

The chief engineer leads everything concerning the assigned vehicle: product, vehicle, sales, and profit planning; industrial design direction; design-engineering oversight; prototype and evaluation supervision; equipment-investment decisions; production-management coordination; and sales promotion. This is broader than any Western program-management role. The chief engineer is accountable not only for whether the car launches, but for whether it sells.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

A Toyota president called the chief engineer "the president" of the assigned vehicle

Adachi captures the scope of the role with a line he attributes to a Toyota president: "For the assigned vehicle model, the chief engineer is the president, and the president is the chief engineer's helper." The statement marks the chief engineer as the single point of accountability for the whole product, not a coordinator within it.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

A chief engineer is drawn from career functional engineers, then groomed over years

A chief engineer is drawn from engineers who have spent a career in one functional area, such as engine, body, or chassis, usually rising to lead it. Such an engineer is then groomed and selected for the role over years. Around the time of appointment, a chief engineer typically has about two decades of engineering experience; the youngest are usually in their forties, more senior ones in their fifties.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The chief engineer sits outside the functional line with no direct reports

Once appointed, the chief engineer no longer sits inside any one functional area and has no direct reports in the departments. Functional engineers remain in their specialist groups — body, chassis, powertrain, manufacturing, purchasing — to develop deep expertise, and the chief engineer pulls them together for the vehicle program. This matrix structure preserves both specialist depth and product coherence.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

"主査" means "chief investigator" or "lead examiner," translated as Chief Engineer

主査 combines 主 (chief, primary) and 査 (investigate, examine). The literal meaning is closer to "chief investigator" or "lead examiner" than to "chief engineer," reflecting the role's emphasis on examining and integrating work across functions rather than directing it. Toyota's English publications translate shusa as "Chief Engineer" (CE), now the standard term inside Toyota and in the lean product-development literature.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

A single midsize vehicle program runs to over 500,000 design-and-test hours

Hori compares a chief engineer's work to "top management of a midsize company driving company management." By his account a single midsize vehicle takes over 500,000 working hours for design and testing alone, more than 100,000 person-days once production engineering and factory preparation are included, and over 10 billion yen in development cost and equipment investment.

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

The chief engineer's real power is signing every engineering drawing before release

For a role with little command authority, the chief engineer's real lever is approval. Historically, every engineering drawing — engine, transmission, body, component — required the chief engineer's signature before it could be released. Nothing was authorized to be built until the chief engineer had signed off. That approval gate, backed by the technical competence to use it, gives a staff position a veto over what the line engineers produce.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

"If the shusa says no, that drawing does not live"

Akihiro Wada, who served as chief engineer for over ten years before becoming Executive Vice President for engineering, described the drawing-approval power directly: "If the shusa says no, that drawing does not live." The chief engineer does not manage the engineers, but controls the product through this sign-off.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

The drawing signature gives technical veto power to a staff position

The sign-off makes the chief engineer's authority real without line authority over people: a staff position holding a veto over the output of the line engineers. The power is over product-and-process design decisions, not over the engineers themselves. This separation of product authority from people authority is the mechanism that makes the role work.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

No one could review every drawing; the discipline was that departments believed they were inspected

No chief engineer could check every drawing in detail. Wada reviewed stacks of them each morning and worked by judgment; a messy drawing usually hid a struggling design. But his ninth rule names the real mechanism: "It may be impossible to review every drawing today, but design departments must always believe they are being inspected." The discipline mattered more than any single signature.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Wada held that chief engineers at other companies do not have this approval authority

Wada is emphatic that chief engineers at other automakers do not hold the engineering-drawing approval authority. That technical veto over engineering output is what set the Toyota chief engineer apart from chief-engineer roles elsewhere, which carry the title without the functioning power.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

The paper signature faded with CAD, but the approval principle persists

The physical drawing signature has faded with CAD and digital development, but the principle has not. The chief engineer still holds the approval every design must pass, now through digital workflows rather than a stack of drawings on a desk. Wada, speaking in 2008, noted that complete review of every drawing was already impossible in practice.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

The chief engineer forms a "CE image" — keywords and a vehicle outline

Kitagawa describes the concept process in stages. The chief engineer gathers marketing information, sales input, quality data, and competitor analysis, and from these forms what Kitagawa calls the "CE image" (CE像): development keywords and a vehicle outline of key dimensions, performance targets, design image, selling points, and price range. At this stage, "cost and development-cost constraints are temporarily placed at the edge of the mind, and dreams and ideals are also included."

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/learning/chief-engineer

The CE image is expressed as a 1/5-scale package drawing, "the floor plan of a house"

The CE image is expressed as a basic layout drawing, often a 1/5-scale package drawing that Kitagawa compares to "the floor plan of a house." This package drawing is the chief engineer's primary artifact. It is the concrete mechanism by which the chief engineer controls the vehicle's character, and all engineering departments design to it.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/learning/chief-engineer

The CE image becomes the "CE concept," the development-decision proposal

After adjustment through discussion with sales, design, engineering, production engineering, plants, quality assurance, and purchasing, the CE image becomes what Kitagawa calls the "CE concept" (CE構想): the development-decision proposal submitted for top-management approval. In practice the chief engineer has already explained the contents to top management informally and obtained consent in advance, so the formal meeting ratifies what has already been agreed.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/learning/chief-engineer

Cost is part of development from the start, not the finance department's problem

Cost is not an afterthought and not finance's problem. It is part of product development from the beginning, managed through 原価企画 (genka kikaku, target costing). Kitagawa frames it as cultivation: "The CE must cultivate the field of cost honestly, steadily, and thoroughly, and achieve the cost target." The target is broken down by vehicle area, part, material cost, processing cost, and tooling cost.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/learning/chief-engineer

The chief engineer must be able to reduce cost down to the part's manufacturing process

Hori adds the engineering dimension to cost: "Especially for reducing the cost of parts, the chief engineer needs the ability to reduce cost by going as far as the manufacturing process of the parts." The chief engineer must study part structures, propose structures that are easier to manufacture, and reduce cost in a way that parts makers themselves accept. Simply bargaining down purchase prices is not cost planning.

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

On the Mark II, the team cut equipment investment to drive a self-reinforcing volume cycle

Adachi gives a strategic cost example. On the Mark II program, the chief-engineer group deliberately held equipment investment to 70% of target sales volume and cut the investment amount 30% below initial proposals. The reasoning: lower per-unit depreciation would enable a lower selling price, which would drive volume. The cycle was self-reinforcing.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

Genka kikaku adapted aviation weight-budgeting logic to cost

Target costing as practiced by the chief engineer traces in part to Hasegawa, an aeronautical engineer, who adapted aviation weight-budgeting logic to cost management. Just as an aircraft has a fixed weight budget allocated across systems, the vehicle has a target cost allocated across subsystems, with tradeoffs managed across the whole vehicle to hit profitability.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

Much of the chief engineer's preparation happens before a program is approved

A great deal of a chief engineer's work happens before a program is officially approved. Hori describes building advance trial vehicles, testing new concepts, and checking technical feasibility well before the company has authorized the work — done informally, "by asking colleagues who were enthusiastic about improving performance, or by arranging to use leftover budgets from other projects."

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

The advance groundwork runs on networking, not authority

The preparation done before approval runs on the chief engineer's networking — relationships and reputation across departments — rather than on authority. People pitch in voluntarily because they trust the chief engineer and think the work is worth doing. This is standard practice, not an exception.

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

Chief engineers can be removed mid-project by superiors in the Planning Department

Hori is unusually honest about the role's vulnerabilities. Chief engineers can be removed mid-project by superiors in the Planning Department. In one case he describes, a veteran chief engineer was replaced one year before production start, after being responsible for more than three years from the start of planning.

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

A chief engineer must manage upward as well as outward

Having the best concept means nothing if the chief engineer cannot maintain a relationship of trust with the directors above. Hori describes being personally removed from cost-estimation assignments when his honest numbers were higher than what management wanted to see. Managing upward is the unglamorous reality behind the "responsibility without authority" principle.

Shigeyuki Hori, Automotive Planning and Development — artoflean.com/learning/chief-engineer

The system has run continuously since Kenya Nakamura and the Crown in 1953

The chief engineer system has operated continuously since Kenya Nakamura was appointed the first shusa for the Crown project in 1953. It emerged because the technical demands of a modern passenger car had become too interdependent for the functional departments to manage in isolation: each optimized within its own domain, producing vehicle-level conflicts that no one was accountable for resolving.

Toyota 75-Year History; Art Smalley, Art of Lean — artoflean.com/reference/shusa

On May 1, 1953 Toyota created the shusa office and named Nakamura the first shusa

On May 1, 1953, Toyota reorganized its engineering departments and created a project office (主査室, shusa-shitsu). Kenya Nakamura was appointed the first shusa for the Crown (RS) development. Eiji Toyoda created the role and deliberately placed it "outside the organization," giving Nakamura responsibility for the whole vehicle without ranking him above any functional department head.

Toyota 75-Year History; Art Smalley, Art of Lean — artoflean.com/reference/shusa

Nakamura established the role through results, not written policy

What Nakamura established was not a written policy but a practice so successful it became culture. As Wada puts it, "Nakamura left such magnificent results that across the entire company, a mood developed that the shusa's word is the president's word. It spread as a kind of unwritten law." Adachi confirms the system "had no written regulations"; it was carried forward by custom and results.

Akihiro Wada, Oral History (2008); Eiji Adachi (2014) — artoflean.com/learning/chief-engineer

Nakamura earned cross-functional trust as a body engineer who built Toyota's 2,000-ton press

Nakamura established the role's legitimacy through personal credibility. A body engineer who had built Toyota's in-house 2,000-ton press, he understood functional constraints deeply and earned trust across departments. He led by walking the floor, engaging directly with engineers in every department, and holding sign-off authority on every engineering drawing.

Toyota 75-Year History; Art Smalley, Art of Lean — artoflean.com/reference/shusa

Tatsuo Hasegawa turned one man's practice into a scalable system

If Nakamura invented the practice, Tatsuo Hasegawa turned it into a system. An aeronautical engineer who had designed high-altitude interceptors during the war and joined Toyota in 1946, Hasegawa brought a systems-engineering mindset. Where Nakamura led by example, Hasegawa codified the role.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Hasegawa served as Nakamura's deputy on the Crown, then led major programs

Hasegawa served as Nakamura's deputy (副主査, fuku-shusa) on the Crown, then became a chief engineer in his own right. He led the Publica, Sports 800, the first-generation Corolla, the Celica, and the Carina, applying and extending the role across program after program.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Hasegawa wrote the Ten Rules and established the Product Planning Office in 1965

Hasegawa codified the role in two lasting ways. He wrote the Ten Rules for the Chief Engineer, the canonical statement of what an effective chief engineer should be and do, and in 1965 he established the Product Planning Office, the organizational home that let the system survive beyond its founders.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The Product Planning Office is a staff department within engineering

The chief-engineer function is housed in the Product Planning Office (製品企画室), a staff department within the engineering division. This is the organizational home that lets the chief engineer carry product responsibility without sitting in the engineering line. Multiple chief-engineer groups share an open floor without partitions, so that consulting a neighboring group about past experience or similar problems is part of daily life.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

The chief-engineer office grew from a handful of CEs to ten or twenty by the 1980s

The Product Planning Office grew from roughly four to six chief engineers in the 1950s and 1960s to ten to twenty by the 1970s and 1980s, one per vehicle model. Information-sharing across the open floor was judged to outweigh any competitive-intelligence risk between programs.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

Three Toyota chief engineers each wrote their own principles, and the lists converge

Hasegawa, Wada, and Kitagawa each set down their own guiding principles for the role: Hasegawa's Ten Rules, Wada's ten kokorogake (心掛け, "things to keep in mind"), and Kitagawa's seventeen. They were written years apart, for different reasons, with no coordination, yet they converge on the same disciplines — curiosity treated as an obligation, honesty with the people who do the work, integration across the whole vehicle, and developing the next chief engineer. That convergence is the evidence that the mindset is the transmissible content of the job, not one person's temperament.

Akihiro Wada, Oral History (2008); Art Smalley, Art of Lean — artoflean.com/articles/chief-engineer-mindset

Hasegawa's first rule: have your own plan, but do not over-dictate

The chief engineer should not arrive empty-handed, but should not over-dictate either. Hint gradually to build trust and direction rather than imposing. The aim is to lead the program's direction without crushing the engineers' own thinking.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's second rule: always learn broad knowledge

Always learn broad knowledge. Expertise outside the chief engineer's own field lets the chief engineer see a problem another way. Curiosity past one's specialty is treated as an obligation of the role, not a personal trait.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's third rule: cast a wide net, because the early survey stage can decide the project

Cast a wide net. How the chief engineer moves at the early survey stage can decide the project's fate. Decisions taken before a program is even approved set the limits on everything that follows.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's fourth rule: pour in all your wisdom and put your body on the line

Concentrate everything on the project; when seriousness shows, people follow. Put your body on the line. The chief engineer earns followership through visible, total commitment rather than position.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's fifth rule: do not find repetition tiresome; repeat your intent at least five times

Do not find repetition tiresome. Reflect daily, and repeat your intent to collaborators at least five times. A leader without command authority must make the concept land by saying it, and saying it again.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's sixth rule: never blame others, because authority has never existed — only persuasion

Never blame others; you own the result even if it means changing the system. This rule contains the principle at the heart of the role: "Authority has never existed. All you have is persuasion. If it is truth, it has infinite power."

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's seventh rule: have confidence, and do not show your wavering

Have confidence in yourself. Do not waver, or at least do not show it. In trouble, a good idea always comes. The organization moves on the chief engineer's conviction, so visible doubt is costly.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's eighth rule: the chief engineer and assistants are a single persona

The chief engineer and the chief-engineer assistants are a single persona. The chief engineer is not a manager, and there is no hierarchy in engineering. Correct how the work is done, never the result, and when you want to scold, scold yourself.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's ninth rule: use no tricks, because face, backroom deals, and rank never last

Do not use tricks. Face, backroom deals, and rank never last. The only durable currency in the role is technical truth, which is why the chief engineer is built to lead without leverage.

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Hasegawa's tenth rule lists the qualities a chief engineer needs, ending in "desirelessness"

The tenth rule lists the qualities a chief engineer needs: knowledge, technical ability, experience, insight, judgment, decisiveness, magnanimity, composure, concentration, vitality, leadership, expressiveness, persuasiveness, and flexibility. It closes with a paradoxical final quality — "the desire called desirelessness."

Tatsuo Hasegawa, Ten Rules for the Chief Engineer — artoflean.com/articles/chief-engineer-principles

Wada's first rule: think habitually and keep widening your knowledge

Think habitually. Stay curious about everything and keep widening your knowledge. Wada placed continuous curiosity first, the same discipline Hasegawa and Kitagawa each put near the top of their own lists.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's second rule: give concrete instructions, because winging it is the most shameful thing

Give concrete instructions. Winging it is, in Wada's words, the most shameful thing. A chief engineer who is vague forces the engineers to guess his intent and cannot hold them to a result.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's third rule: if a subordinate says "you told me to," never deny giving the instruction

If a subordinate says "you told me to," never insist "I never said that." When you are wrong, say so at once and take the rework on yourself. A leader who runs entirely on trust cannot afford to spend any.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's fourth rule: raise objections at once, and on a 40/60 call, say yes

While someone explains a proposal, line up your objections and raise them the moment they finish. Avoid saying yes and then reversing to no later. On a 40/60 call, say yes — the other person's motivation matters more than the last ten percent of the decision.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's sixth rule: decide fast, because poor deliberation is no better than resting

Decide fast. Poor deliberation is no better than resting. Wada kept a clean desk with nothing carried over and decided on the spot, so work never piled up behind him.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's seventh rule: cast a wide net in development, but watch efficiency

Cast a wide net in development, but watch efficiency. Explore broadly at the front of a program, while keeping the cost and time of that exploration in check.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's eighth rule: avoid large meetings, because while a meeting runs, work has stopped

Avoid large meetings. While a meeting runs, consider that work has stopped. Wada sent people back to work once they had cleared the two or three items that involved them, treating the rest of a meeting as a form of resting.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's ninth rule: you cannot review every drawing, but departments must believe they are inspected

You cannot review every drawing, but the design departments must always believe they are being inspected. This is the working mechanism behind the drawing sign-off: the discipline comes from the belief in scrutiny, not from reading every page.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Wada's tenth rule: develop your assistants, and make the effort to trust and delegate

Develop your chief-engineer assistants, and make the effort to trust and delegate to them. The role is built to be handed on, so growing the people who come next is part of the daily work.

Akihiro Wada, Oral History (2008), 心掛け — artoflean.com/articles/akihiro-wada-chief-engineer

Kitagawa's seventeen rest on three "hearts": curiosity, consideration, and imagination

Kitagawa says three dispositions underlie all seventeen of his principles: curiosity, consideration for others, and imagination. Curiosity is why a chief engineer has to know how everything is made and costs; consideration is why he persuades rather than commands and looks after his own group; imagination is why he can hold a picture of a car that does not yet exist and steer a thousand specialists toward it.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 1: vehicle planning and development are passion

Vehicle planning and development are passion; keep thinking about the product asleep or awake. Kitagawa puts ownership of the concept first — the product should occupy the chief engineer's mind continuously.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 2: acquire the ability to arrange work so high goals can be completed

Acquire the ability to arrange work so that high goals can actually be completed. Ambition is not enough; the chief engineer must structure the program so demanding targets are reachable.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 3: have stronger intellectual curiosity than anyone else

Have stronger intellectual curiosity than anyone else. This is curiosity, the first of the three hearts, stated as a daily obligation — the same discipline Hasegawa and Wada each placed near the top of their lists.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 4: acquire the ability to express thoughts and ideas clearly

Acquire the ability to express thoughts and ideas clearly. A chief engineer who cannot make the concept legible cannot align a thousand specialists to it, since he has no authority to compel them.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 5: build a broad network of people who will help when it matters

Build a broad network of people who will help when it matters. Much of the chief engineer's work runs on relationships and reputation rather than authority, so the network is built deliberately, in advance.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 6: act as the personnel and general-affairs chief for your own group

Act as the personnel and general-affairs chief for your own group. The chief engineer looks after the people in the chief-engineer room, treating their welfare and development as part of the job.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 7: check drawings honestly, steadily, and thoroughly

Check drawings honestly, steadily, and thoroughly. The drawing sign-off is the chief engineer's real power, and it means nothing unless the checking behind it is genuine.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 8: cultivate the field of cost honestly and hit the cost target

Cultivate the field of cost honestly and steadily, and hit the cost target. Kitagawa treats hitting cost as one of the unglamorous core duties of the role, alongside checking drawings and looking after his own group.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 9: do not leave selling to the sales division

Do not leave selling to the sales division. Think for yourself about how to sell. The chief engineer is accountable for whether the car sells, so the market is his responsibility, not only the showroom's.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 10: use experts well where you lack knowledge, but never neglect your own study

Use experts well where you lack knowledge, and never neglect your own study. The chief engineer leans on the assistants' depth in each function while continuing to widen his own knowledge.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 11: lead by example in genchi genbutsu, using all five senses

Lead by example in genchi genbutsu — going to the actual place and using all five senses. The chief engineer forms judgments from the real thing in the real place, not from reports.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 12: practice dialogue-based development with users early

Practice dialogue-based development with users early, and when in doubt, observe customers. Kitagawa studied where young buyers gathered before the bB, down to a car-audio gathering at Daikoku Pier, and built the car around what he saw.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 13: treat delay in the development schedule as the greatest shame

Treat delay in the development schedule as the greatest shame. The chief engineer owns the program's timing, and on the bB the team checked drawings three times before release so nothing arrived late and forced a delay.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 14: work to develop young people and the next generation of chief engineers

Work to develop young people and the next generation of chief engineers. As with Hasegawa and Wada, the list ends up at succession: the role is built to be handed on.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 15: be the strongest salesperson for a new market, and go there yourself

Be the strongest salesperson for opening a new market, and go to that market yourself. For the bB, Kitagawa previewed the car at a modified-car show before its official debut, breaking Toyota's own launch habits to reach young buyers.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 16: never forget gratitude toward everyone who supports you

Never forget gratitude toward everyone who supports you. A chief engineer leads a thousand specialists who do not report to him, so the relationships that make the work possible are acknowledged, not assumed.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Kitagawa's principle 17: cultivate the physical strength and willpower to fight for long hours

Cultivate the physical strength and willpower to fight for long hours. The scale of a vehicle program — hundreds of thousands of engineering hours over years — makes stamina part of the qualification.

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/articles/naoto-kitagawa-chief-engineer

Technical competence is the precondition: the chief engineer must argue on technical grounds

On what makes the system work, Wada is as frank about its weaknesses as its strengths. The first requirement is technical competence: the chief engineer must be able to argue with engineers on technical grounds. Without this the drawing signature is meaningless, because the engineers will know the chief engineer cannot actually evaluate their work.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Deep expertise in one domain is "the first condition"

The chief engineer must be someone who can stand equal to a department head in their home engineering domain. Wada calls this "the first condition." If the chief engineer has that depth in one area, such as engine, body, or chassis, then the chief-engineer assistants cover the other areas.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Experience across multiple model cycles is essential; one cycle is not enough

One model cycle is insufficient. The best chief engineers accumulate judgment across multiple vehicle generations; Wada spent over ten years in the role. When modern chief engineers do only one cycle and rotate out, problems follow. A new chief engineer who thinks "now I can build the car I want" may do what Wada calls "outrageous things," and the organization, conditioned to follow, will follow in the wrong direction.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Real oversight comes from a responsible executive who is also an engineer

The responsible executive (担当役員, tantō yakuin), the board-level officer in charge of that area of development, must check the chief engineer's work. This is real oversight, not a rubber stamp: at Toyota these executives were themselves engineers who rose through the company, so they could genuinely judge the call. The board was entirely internally promoted until Toyota named its first outside directors in 2013.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Wada names the system's primary weakness: the whole company moves on the chief engineer's opinion

Wada identifies the system's primary weakness as the flip side of its strength. The whole organization moves easily on the chief engineer's opinion, which makes it easy to unify in one direction. A wrong opinion carries everyone down the wrong path. In his words: "The whole company moves easily on the shusa's opinion — easy to unify in one direction. The downside is the opposite."

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

The system depends on a company-wide culture that cannot be decreed

The company-wide culture must treat the chief engineer's word as authoritative. This developed organically from Nakamura's track record, not from formal decree, which is why other companies could copy the role but not the culture. When Mercedes-Benz sent technical directors to Toyota, their questions focused on "why does the shusa system work?" The answer is not structural but cultural, built over decades.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

A succession pipeline keeps the role continuous, not dependent on one person

Roughly ninety-nine percent of new chief engineers come from having been chief-engineer assistants for that vehicle line. The best candidates are kept in the group long-term rather than rotated too frequently. Wada maintained a system where "information was shared so the shusa could be replaced at any moment." The result was continuity, not dependency on one person.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

The chief-engineer room is a team, not a lone hero

The chief-engineer room (主査室) is a team: one chief engineer with five to seven chief-engineer assistants (主査付き, shusa-tsuki), each covering a different functional area. Both Hasegawa and Wada stress developing and trusting these assistants. The role is not heroic individual leadership; the system produces continuity rather than dependence on a single person.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The first Prius is the best-documented test of the chief engineer system under pressure

The first Prius (1993–1997) is the best-documented case of the chief engineer system under pressure, and an unusual one in Toyota's history. It was Toyota's first hybrid and the world's first mass-production hybrid car. There was no existing model to copy and no proven technology to carry over: the powertrain, the key engineering decisions, and even the development method had to be created from scratch.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Uchiyamada led the Prius with no prior chief-engineer experience, treated as an asset

Takeshi Uchiyamada led the G21 project as chief engineer with no prior chief-engineer experience. His lack of product-development preconceptions was treated as an asset for a car with no precedent. He owned the vehicle concept, ran the development, and negotiated his own terms with management.

Art Smalley, Art of Lean — artoflean.com/articles/uchiyamada-prius-chief-engineer

Uchiyamada negotiated milestone management with the right to push the schedule for quality

Uchiyamada negotiated milestone management with management, keeping the right to push the schedule back if quality could not be built in. The team worked in a single room with all project information posted on the walls. Open big-room working and visual wall displays were not new at Toyota, but Uchiyamada systematized the room, the roles, and the practices into what became the obeya (大部屋) method. Production engineering was included from the start.

Art Smalley, Art of Lean — artoflean.com/articles/uchiyamada-prius-chief-engineer

On the Prius the chief engineer did not act alone — the vice president set the stretch target

The Prius shows the chief engineer operating inside a chain of authority, not alone. Wada, as technical vice president, overruled the team's 1.5x fuel-economy target and demanded 2x. This deliberate stretch forced the move to hybrid power, and he also made direct technical calls along the way. President Okuda set and locked the launch deadline.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The chain of authority holds because each level trusts the one below it

On the Prius, Uchiyamada owned the product. The vice president set the challenge and could have ended the project. The president committed the company. The system holds because each level trusts the one below it, and that trust rests on technical competence at every level.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

A Western program manager coordinates schedule and budget; the chief engineer differs in kind

In most Western companies, program managers coordinate schedule, budget, and communication across functions; they are administrators of the development process. The Toyota chief engineer is different in kind: a senior technical leader who owns the product concept end-to-end — what the car should be, not just when it will be done.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

Clark and Fujimoto called the role the "heavyweight product manager"

Academic researchers Clark and Fujimoto, in their 1991 research, termed the role the "heavyweight product manager," distinguishing it from the "lightweight" coordinators common in Western firms. The shusa fits the label, and it is the most accurate Western term for the role.

Clark & Fujimoto, Product Development Performance (1991) — artoflean.com/learning/chief-engineer

"Heavyweight project manager" still understates the Toyota chief engineer

Even the heavyweight-project-manager label understates the role. The Toyota chief engineer also holds approval over engineering output, owns product cost down to the part level, and is accountable for whether the car sells. That is scope well beyond coordinating a project.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The chief engineer forecasts sales and competes with the Sales division on the forecast

Accountability for the product extends to the market. Adachi quotes a Toyota president: "The chief engineer himself should forecast sales, and then compete with Sales to see whose forecast is correct." The chief engineer is accountable for whether the car sells, not only whether it launches.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

Withholding command authority is deliberate, and it trains the chief engineer

Command authority was withheld on purpose. As Adachi explains, "if the chief engineer persuaded sincerely, the other party's heart should move… that process ultimately trained the chief engineer." The constraint forces persuasion, which forces technical competence, which builds the institutional trust that makes the system work.

Eiji Adachi, Toyota Product Development (2014) — artoflean.com/learning/chief-engineer

Outside accounts of the system reflect limited access, not the whole

Various outside observers have studied parts of the system — notably Allen Ward and Durward Sobek on set-based design, and James Morgan and Jeffrey Liker on product development broadly. These accounts reflect limited access to specific parts of Toyota's development process and should not be taken as comprehensive descriptions of the whole system. The distinctive sourcing here is the chief engineers' own Japanese-language accounts.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

Misconception: the chief engineer is a project manager with a different title

The chief engineer owns the product, not the project plan. A project manager coordinates timeline and budget. The chief engineer decides what the car is, signs the engineering drawings, owns the cost structure, and is accountable for whether it sells. Companies that fill the title with schedule-and-status managers miss the point.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Misconception: the chief engineer should have line authority to be effective

Giving the chief engineer line authority would destroy the mechanism that develops the role's capability. The constraint forces persuasion, which forces technical competence, which builds the institutional trust that makes the system work. When the chief engineer is also the boss of the engineers, the creative tension disappears and engineers comply rather than challenge. Toyota designed it this way deliberately.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Misconception: strong leadership skills alone qualify someone to be a chief engineer

Technical depth is the first condition. The chief engineer must be able to argue with a department head on equal terms in at least one engineering domain. Without this the drawing signature is a rubber stamp and functional engineers will ignore the chief engineer's judgment. Leadership skills matter, but they are built on top of engineering credibility, not substituted for it.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Misconception: the role is heroic individual leadership

The chief-engineer room is a team of one chief engineer and five to seven assistants, each covering a function. Both Hasegawa and Wada stress developing and trusting these assistants, and information is shared so that the chief engineer could be replaced at any moment. The system produces continuity, not dependency on one person.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Misconception: rotating people through the role quickly develops more leaders

Wada is explicit that experience across multiple model cycles is essential. Chief engineers who do only one cycle and rotate out lack the accumulated judgment that makes the role effective. The system's health depends on chief engineers serving long enough to internalize the lessons of their own mistakes.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Misconception: the system can be copied by creating the org-chart position

Other automakers have chief-engineer roles. But without the drawing sign-off authority, the institutional culture that treats the chief engineer's word as authoritative, the deep succession pipeline, and the informal groundwork done before approval, the title becomes coordination without teeth. Wada observed this across every competitor he encountered.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

In 1989 the title formally changed from 主査 to chief engineer

In August 1989, the title was formally changed from 主査 (shusa) to チーフエンジニア (chief engineer), as part of a broader organizational flattening. The engineering division had grown to roughly 12,000 people and the term 主査 had spread to many departments. "Chief Engineer" distinguished the vehicle-program leader, with sub-chief engineers beneath still called shusa.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

In 1992 Toyota restructured into Development Centers organized by platform

On September 25, 1992, Toyota restructured into Development Centers organized by platform type: rear-wheel-drive passenger vehicles, front-wheel-drive passenger vehicles, commercial vehicles and RVs, and element technologies. This added a platform-governance layer above the chief engineer, encouraging parts commonality and shared architectures while preserving the chief engineer's role in vehicle concept and customer focus.

Toyota 75-Year History; Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Platform governance created a standing tension with chief-engineer autonomy

By the early 1990s, strong chief-engineer autonomy produced excellent individual vehicles but also avoidable variation across similar models, as each chief engineer justified unique parts for their own program. Platform governance was meant to curb this. The balance is genuine and ongoing: when platform standardization becomes too strong, the chief engineer's ability to differentiate the vehicle for the customer can be diluted.

Art Smalley, Art of Lean — artoflean.com/reference/shusa

Under TNGA and the in-house company system, the core principle was preserved

Under Akio Toyoda, the Toyota New Global Architecture (TNGA) standardized platforms across vehicle lines. In 2016 Toyota reorganized product development from the development-center structure into a product-based in-house company system: seven in-house companies, each with end-to-end responsibility for its product line. Through every reorganization, the core principle was preserved: one person, accountable for the whole vehicle.

Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

The core principle has survived every restructuring

The core principle — one person accountable for the whole vehicle, leading through technical competence and persuasion rather than hierarchical authority — has survived every restructuring. Whether it has been diluted in practice is a question the primary sources raise but do not definitively answer. Wada, speaking in 2008, expressed concern that shorter chief-engineer tenures and organizational complexity were weakening the system.

Akihiro Wada, Oral History (2008); Art Smalley, Art of Lean — artoflean.com/learning/chief-engineer

Becoming a chief engineer takes about two decades and is learned on the job

There is no fixed timeline and no dedicated chief-engineer school. By the time someone is appointed they typically have around two decades of engineering experience. Chief engineers build careers in a functional engineering area, transfer to the Product Planning Office, train as chief-engineer assistants, and eventually become chief engineers. The learning is on-the-job: assignment, mentorship, and the experience of struggling with real products. Kitagawa notes, "A person cannot learn the CE role only by reading manuals."

Naoto Kitagawa, Toyota Chief Engineer's Work — artoflean.com/learning/chief-engineer

The role's early figures had aviation backgrounds, but the system is Toyota's own

Several early chief engineers, including Nakamura and Hasegawa, had aviation backgrounds. However, Wada attributes the system specifically to Nakamura's practice at Toyota, not to any aviation precedent. The aviation connection shaped the individuals, but the system was built inside Toyota through results.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer

Rival automakers studied the system; none reproduced it

Senior executives from rival automakers, including Ford, BMW, and Mercedes-Benz, came to Toyota to ask how the chief engineer system works. Other companies have a chief-engineer title, Wada observes, but not the functioning role. He considers the integrated shusa, grounded in deep engineering authority, particular to Toyota.

Akihiro Wada, Oral History (2008) — artoflean.com/learning/chief-engineer