Lean is one of the most pervasive phenomena in management practice. Unsurprisingly, it has also been a persistent topic for empirical scholars across management and engineering disciplines. On the surface, the interest appears to continue to surge, but a deeper look suggests that lean is peaking, at least as a subject of academic interest.
Most extensive review of the lean literature
The evidence stems from the world’s most extensive review of the lean literature. Our article “The evolution of lean: taking stock and looking ahead,” recently published in Foundations and Trends in Technology, Information and Operations Management, covers 35 years of academic publications since the term “lean” was introduced in 1988.
We used Web of Science to construct two datasets: one consisting of 6,920 unique articles directly addressing lean, and the other comprising all 345,855 references cited in the first dataset, of which 163,836 are unique. This large-scale dataset enabled us to statistically and bibliometrically analyze lean from an evolutionary perspective.
More papers, but a declining share
We looked at lean as an evolving business phenomenon. Drawing on the data, we approximated four time periods in the evolution of lean:
- Pre-1988 was the lean incubation period,
- 1988–2003 was the lean installation period,
- 2004–2019 was the lean deployment period, and
- 2020–today is the lean exhaustion period.
Lean research has grown exponentially over the past 35 years. The figure below illustrates the year-by-year publication counts for all lean articles. It presents a conservative estimate, as we included only articles that specifically used the word “lean” in the title, abstract, or listed keywords. To check whether the growth of the lean literature is entirely due to the expansion of less rigorous journals, we repeated the analysis, including only the Financial Times top-50 journals. We found that lean research is still consistently published in top journals, too.
However, absolute growth numbers can be misleading if they merely reflect a general trend in the academic literature. We therefore also compute the relative share of lean articles compared to the overall literature. To do this, we identify the 50 journals with the most publications on lean, then divide the number of lean articles by the total number of articles published in those journals each year. This critical analysis is unique to our research.
The results in the figure below show that lean’s relative share in these 50 “lean-friendly” journals has been slowing down since 2012. This is an interesting observation, indicating that lean research has entered an exhaustion period in scholarly work.
Business phenomena that enter the exhaustion period tend to become less innovative. Indeed, much of the scholarly literature on lean today is repetitive or incremental. With thousands of articles published, it becomes impossible for researchers to keep up with the literature, increasing the risk of going in circles. The increasing use of generative AI in scholarly work may temporarily boost publication numbers, but not their novelty.
Popular books are most influential
The best-selling books on lean are cited far more often than the most cited academic articles. In our lean-centered dataset, the most cited book, The Machine by Womack, Jones, and Roos (1990), has received more than twice as many citations as the all-time-most-cited academic article, “Lean manufacturing: context, practice bundles, and performance” by Shah and Ward (2003). On Google Scholar, the ratio is 6:1.
Other very influential books include Lean Thinking by Womack and Jones (1996), Toyota Production System by Ohno (1988), The Toyota Way by Liker (2004), and the VSM reference Learning to See (Rother and Shook, 2003). All of these are cited more often than Shah and Ward’s highly influential 2003 article (though, impressively, Rachna Shah and Peter Ward also published the second-most-cited lean article in 2007).
Academics can target many different journals with lean research. If they seek impact, they are better off publishing their research in top-tier journals. On average, each lean article published in the Journal of Operations Management attracts 116 citations from other lean articles. In Production and Operations Management, that number is 36 citations. This is higher than the average for lean articles published in non-FT50 journals, where a publication in the highest-impact journal, the International Journal of Operations and Production Management (IJOPM), attracts, on average, 31 citations. But of course, there is substantial individual variation in citations for papers.
Future of lean research in a digital era
The review article also covers other interesting stats about the lean literature, including knowledge cluster maps, the most prolific journals, the spread across disciplines and geographies, trending keywords throughout lean’s history, lean scholars’ methodological preferences, and research focus. Interested readers can download the article for free here.
Essentially, we do in no way suggest that lean is obsolete or outdated as a concept and philosophy. Quite the contrary, in fact. We still think there are many interesting research questions as lean continues to evolve as a business phenomenon. The review article concludes with a research agenda for lean scholars. For example, there are relevant knowledge gaps regarding lean’s relationship to AI and the evolving geopolitical business environment. Just because lean is maturing doesn’t mean it is dead.
Citation: Netland T., Januszek S., Shah R., Pilkington A. (2026), The evolution of lean: taking stock and looking ahead. Foundations and Trends in Technology, Information and Operations Management, Vol. 20 No. 3 pp. 69–147, doi: https://doi.org/10.1108/FTTOM-11-2024-0121
Download our open-access PDF.
References
- Krafcik, J.F., 1988. Triumph of the lean production system. Sloan management review 30(1), 41-51
- Liker, J.K., 2004. The Toyota way: 14 management principles from the world’s greatest manufacturer. McGraw-Hill, New York
- Ohno, T., 1988. Toyota Production System: beyond large-scale production. Productivity Press, New York, NY
- Rother, M., Shook, J., 2003. Learning to see: value stream mapping to create value and eliminate muda. Lean Enterprise Institute, Brookline, MA
- Shah, R., Ward, P.T., 2003. Lean manufacturing: context, practice bundles, and performance. Journal of Operations Management 21(2), 129-149
- Shah, R., Ward, P.T., 2007. Defining and developing measures of lean production. Journal of Operations Management 25(4), 785-805
- Womack, J.P., Jones, D.T., 1996. Lean thinking: banish waste and create wealth in your corporation. Free Press, New York, NY
- Womack, J.P., Jones, D.T., Roos, D., 1990. The machine that changed the world. Rawson Associates, New York, NY
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