JANUARY/FEBRUARY 2002: INTERVIEW
LEAN TIME, LEAN MEASURES
– By Michael San Filippo
Jim Womack has spent nearly 25 years studying, analyzing and
teaching Lean production. Not only does he think Lean, he speaks
Lean. His words are uninterrupted by pauses, tangents or
uncertainties; they come fast and on target, completely waste free, truly
Lean. Of course, one should expect nothing less from Womack, widely
regarded as the world's foremost expert on Lean production and the
co-author of two books, The Machine That Changed the World and
Lean Thinking, which brought the fundamentals of Lean to a mass
audience in the 1990s. The Lean production philosophy that he extols
is based upon the Toyota Production System; however, he has
advocated its use not only in manufacturing, but in other areas as well,
including health care, construction and distribution.
Lean production has seen a rise in popularity as the U.S. economy has settled into recession:
Lean Thinking, published in 1996, recently resurfaced on the Business Week Best-Seller List.
“Lean Thinking was written for the recession of 1997, which never happened,” Womack says. “It’s
a wonder we sold as many copies initially as we did.
“We ‘Lean’ guys had a tough decade because any moron could make money. It’s hard to be
heard when everyone’s making money. Companies could simply solve problems with more
hardware; they weren’t taking a hard look at their processes. Well, now the ‘90s are over, Clinton
is long gone, the party’s over. And what do you know, now you’ve got to work for a living.
Suddenly people are stopping and saying, ‘We’ve got to take the waste out. We’ve got to get
The term “Lean production” was first identified by Womack, Daniel Jones and Daniel Roos in
1991’s, The Machine That Changed the World. In the book, based on a five-year, $5 million study
of the automobile industry, Womack, Jones and Roos took an in-depth look at the Japanese
manufacturing system, exemplified by Toyota, which combined the best features of craft
production (high-quality, individualized, custom-made products) with mass production
(manufacturing in large quantities to satisfy broad consumer needs at lower prices).
The book, which was one of the first to thoroughly examine Toyota’s highly successful business
system, concluded that Toyota was dominating the automobile industry because it optimized the
value delivered to customers while minimizing the time, human effort and capital required to
create this value.
Womack followed up on this study into Lean production with Lean Thinking, co-authored by
Jones, which provided companies with a practical guide to apply Lean production to their
industry. To become Lean, Womack advises, companies should concentrate on the whole rather
than the parts. “The fundamental objective is to shift the focus of management from the existing
organization, technologies and assets to the product itself,” Womack says. “This will allow
companies to differentiate value from waste.
“Instead of manufacturing products in a disconnected and geographically dispersed process,
companies should recreate their process by working backward from the end product at the point
of delivery to the customer. This permits the product to respond to the needs of the customer
rather than being pushed ahead to keep existing assets and machinery fully occupied.”
In Lean Thinking, Womack highlights five principles to guide managers in the fight against waste:
• Value: Specify value from the perspective of the customer, not the firms, departments and
facilities that comprise the supply chain.
• Value Stream: Identify the value stream for each product or service, comprised of every action
responsible for its design, order and provision. Eliminate actions that create no value.
• Flow: Align all value-creating steps so that the design, order and product itself move steadily
and rapidly toward the customer with no detours, waiting or scrap.
• Pull: Make products flow only at the pull of the customer, so the exact good is provided at
exactly the right time.
• Perfection: Re-evaluate every value stream to make value flow faster at the precise pull of the
According to Womack, by following these principles and implementing a Lean production system,
the amount of effort needed to produce a product can be reduced by 50 percent to 75 percent;
time elapsed from order to delivery can be reduced by 90 percent; and inventories of work-in-
process and finished goods can be reduced by 90 percent.
Lean Production in Lean Economies
It is only in times of great economic stress, Womack says, that advances in Lean production are
made. “Taiichi Ohno at Toyota was able to push the Toyota Production System [TPS] through the
entire Toyota Motor Co. in 1950 during the great crisis that left Toyota on the brink of bankruptcy,”
he says. “He had been trying for several years but was making slow progress until the collapse in
sales that forced Toyota to reduce its work force permanently by 25 percent. Toyota offered
employment guarantees to those who remained, provided they learned to work together in new
“The first oil shock of 1973 was the moment Toyota seized to push TPS through its entire supply
base in Japan. Ohno had formed the Operation Management Consulting Group at Toyota in the
late 1960s for the purpose of teaching TPS to suppliers, but there was little progress until many
faced bankruptcy in the economic crisis of 1973-1975 unless they learned to run their businesses
according to Lean principles.
“The recession of 1981-1982, coinciding with the arrival of the first Japanese transplant, was the
first time American car companies took Lean thinking seriously.
“The recession of 1991-1992 marked a great leap in awareness of Lean thinking by the
aerospace industry, general manufacturing and the European motor industry. This generated the
Lean conversion stories at Pratt & Whitney, Wiremold, Lantech and Porsche that Dan Jones and I
told about in Lean Thinking.”
Womack rejects the claims made after Sept. 11 that certain elements of Lean production are
impractical due to additional security and subsequent delays in border crossings, and that
businesses should increase inventories to buffer against supply chain interruptions. “The
problem, of course, is that this advice is wrong, and it’s hurtful to those [businesses] implementing
Lean,” Womack says.
Unless a product can flow continuously from start to finish, or demand is perfectly consistent,
there will be points where inventory must be present to supply customers effectively. While a
certain amount of inventory is acceptable to cover potential delays, Womack warns against
stockpiling massive amounts of parts or products.
“Extra stocks should be kept aside – out of the path of the value stream but not in some remote
warehouse – and their presence does not in any way effect the logic of Just-In-Time parts
supply,” Womack says. Each downstream process needing parts should still signal directly to the
upstream supplying process when more parts are needed and these should be supplied
frequently in small lots. The one adjustment necessary over time, if bottlenecks persist at border
points, may be longer reorder times. Otherwise Lean production can proceed as in the past.
“However, if you think border crossings will be a problem for you in the future, why not move all
value-creating steps in one place?” adds Womack. “Why not compress your value streams for
each product family to put all of the value creating steps in one area – as at Toyota City – or even
in one facility? Depending on factor costs and customer expectations, the appropriate location
may be in a high labor-cost area – close to end users – or in a low-cost area for price sensitive
products where customers are willing to wait. In either case, you will be better off if as many steps
as possible are colocated.”
Based on his study of the previous two recessions, Womack has outlined the following steps
companies should follow to implement Lean production during the current downturn:
• Assign value-stream managers: Their responsibility should be to map the stream and quickly
implement a future state with lower costs, less inventory and better customer response. “Do not
settle for ‘point interventions’ that improve only one small part of the stream without benefit for the
end customer or your bottom line.”
• Empower value-stream managers: Give these managers full support by removing obstacles to
smoother flow, including outdated facilities, balky internal functions and inefficient relationships
with suppliers. “If the future state looks only a little better than the current state, your firm may not
have a future.”
• Compress value streams: “Consider pulling activities for each value stream back from suppliers
to compress throughput time and take out even more cost while defending your people.”
• Remove waste: Take out all of the excess inventories, space, machines and people from each
value stream as quickly as possible. “Then, when growth resumes, figure out how to increase
output without more inventories, space, machines or people. This is how permanent gains are
• Cash or profits: Decide which of these is your priority. “If you need cash, eliminate inventory and
sell assets immediately. If you need to improve your profitability, remove the inventory and assets
from the value stream to reduce costs but defer disposition until later.”
• Be honest: Tell your people the truth about what needs to be done and do it quickly. “People
can stand the truth. What they hate are lies, drip torture and managers with no believable plan for
Womack is optimistic that further advances in Lean production will occur during this recession, as
they have in the past. “I’m bullish, I think there’s going to be a big leap in Lean consciousness
and implementation in the near future,” he says. “Let’s hope I’m right, and some good will come
out of the bad.”
• In Lean Thinking, authors Dan Jones and Jim Womack extract the
principles supporting lean production from the original lean system, the
Toyota Production System. Then, using examples gathered during a four-
year research effort from diverse industries, such as aerospace,
distribution, capital equipment, wire and cable management, and
automotive, they explain how you can apply the principles. They layout an
action plan for implementation, describe the objectives of a lean
enterprise, and illustrate the benefits lean holds for everyone, including
engineers, line workers, managers and executives.
• The Machine That Changed the World gave lean production its name and
the world its first comprehensive analysis of this revolutionary new way of
working. This lean production classic challenged the fundamental ideas of
how we make things based on a rigorous study of the world automotive