The Power of Habit Summary
The Key Ideas, What Holds Up, and How to Use Them

The Power of Habit explains habits through a three-step loop and stories from labs, companies and social movements. Here are its big ideas in our own words, what later research found about its claims, and a few small practices drawn from the parts that hold up.

About the book

The Power of Habit: Why We Do What We Do in Life and Business is by Charles Duhigg, a journalist who led the New York Times team that won a 2013 Pulitzer Prize for “The iEconomy”, a series on the global economy seen through Apple. Random House published it on 28 February 2012; the hardcover runs to 400 pages. Duhigg’s website says it spent over three years on bestseller lists and has been translated into 40 languages.

It is narrative non-fiction: research on habits told through stories. Part 1 covers the habits of individuals, Part 2 the habits of organisations (Alcoa, Starbucks, Target), and Part 3 the habits of societies, ending with a chapter on free will. An appendix turns the ideas into a four-step guide.

The book is in copyright, so we did not read it in full. We read the publisher’s free excerpt of the first part of chapter 1, the book’s appendix (which the author publishes on his website), his question-and-answer sheet, the library catalogue record, short passages through the Internet Archive’s search-inside tool, and the studies listed below.

The big ideas

1. A habit is a loop

Duhigg describes every habit as three steps: a cue that triggers it, a routine (the behaviour), and a reward. He draws on rat studies at MIT, in which brain activity during a learned maze run came to bunch at the start and the end of the routine. Over time, he argues, the loop runs with little thought.

2. Habits work even without memory

The opening chapter follows Eugene Pauly, known in the research as E.P., whose memory was destroyed by viral encephalitis. He could not remember new facts, yet he could learn routines, which suggests habits are stored apart from the memories we can describe.

3. Cravings drive the loop

The second chapter, “The craving brain”, is about how new habits are created. In the appendix Duhigg writes that rewards are powerful because they satisfy cravings, that each person’s habits are driven by different cravings, and that we are often not conscious of them.

4. The Golden Rule of habit change

You cannot simply delete a bad habit, Duhigg argues; you replace it. Keep the old cue and the old reward, and insert a new routine. He calls this a rule “that study after study has shown is among the most powerful tools for creating change”.

5. Keystone habits

Some habits matter more than others because they set off a chain of other changes. His main examples are exercise for individuals and, for organisations, Alcoa, where, in the book’s account, the chief executive Paul O’Neill made worker safety his first priority.

6. Willpower can become a habit

The Starbucks chapter treats willpower as a skill that can be trained until it is automatic, and as a resource that can run low. The book calls willpower “the single most important keystone habit for individual success”.

7. Organisations and societies run on habits too

Companies study customers’ routines (the Target chapter), and the third part uses habits to explain how social movements happen, with the Montgomery Bus Boycott as its example. The last chapter asks how responsible we are for our habits.

What holds up

The lab stories we could check hold up: the amnesia case is told in line with the published research, and the rat studies are real. The core idea that habits are triggered by cues in a familiar setting is central to habit research. The loop itself is simpler than the research, the “more than 40 percent” figure depends on how habit is measured, and the business and willpower chapters rest on claims that are disputed or that we could not check. The rows below give each claim, the verdict and the source.

What the reward does

This is where the book and some later habit research differ most, so here are the views. In the book, cravings for rewards drive habits. In the model of Wendy Wood and David Neal (2007), goals matter while a habit forms, because they motivate the repetition, but once it has formed, the setting “triggers the associated response without a mediating goal”, and habit associations “do not shift appreciably with current goal states”. On that view, a habit can keep running even when what you want has changed, which is part of why habits are hard to change by wanting something else. Habit researchers do not all agree with Wood and Neal: Kruglanski and Szumowska (2020) argue that “habitual behavior is in fact goal-driven”, and a 2018 study by de Wit and colleagues reported “five failed attempts” to create goal-insensitive habits in people in the lab. The views share the cue; they differ on how much the reward does once a habit is set.

How to use it

These practices come only from the parts that hold up. They describe what people do; what fits your life is your call.

1. Noticing the cue. Since habits are set off by their settings, people who use the book’s method note where they are, the time, who is around, how they feel and what they just did when the urge comes. The five-category list is the author’s checklist rather than a finding, but noticing the setting rests on solid research.
2. Writing the plan as if-then. The book’s fourth step is a plan of the form “at this cue, I will do this”, which psychologists call an implementation intention. Our Atomic Habits summary covers the evidence: such plans help, though the effect is small once publication bias is allowed for.
3. Changing the setting as well as the routine. Wood and Neal’s model points to managing the cue itself, since the setting is what triggers a formed habit. Some people move the cue out of reach or change where they do things.
4. Expecting the old habit back in the old place. Because extinction leaves the original learning in place, a slip in a familiar setting is what the research predicts, not a sign that nothing changed.
5. Giving it weeks to months. In a 2010 study of 96 volunteers, the time for a new daily behaviour to become close to automatic ranged from 18 to 254 days.

Who it’s for, and who can skip it

It suits readers who like ideas told through stories and want a simple model for thinking about routines at home and at work. The opening chapter we read is accurate and well told. The business stories are vivid, but they are stories about single companies, and some of their details could not be checked. Readers who want the practical method can read the appendix alone, which the author publishes free on his website. Readers who already know the habit research, or have read Atomic Habits, will find the core familiar.

If you liked this

• Atomic Habits, summarised: James Clear describes a four-step habit loop (cue, craving, response, reward) and adds a practical system; we check its claims too.
• Grit, summarised, on staying power and deliberate practice.
• Thinking, Fast and Slow, summarised, for automatic thinking and what happened to the willpower research.
• Cognitive biases, checked, including ego depletion and how the replications turned out.

Sources

• C. Duhigg, The Power of Habit: Why We Do What We Do in Life and Business (Random House, 2012): publisher’s page with the free excerpt of chapter 1; the book’s appendix, “A Reader’s Guide to Using These Ideas”; “A Conversation with Charles Duhigg”; the author’s book page and about page; catalogue record and short passages via the Internet Archive’s search-inside tool.
• W. Wood and D. Rünger, “Psychology of habit”, Annual Review of Psychology 67 (2016); W. Wood and D. T. Neal, “A new look at habits and the habit-goal interface”, Psychological Review 114 (2007).
• A. W. Kruglanski and E. Szumowska, “Habitual behavior is goal-driven”, Perspectives on Psychological Science 15 (2020); S. de Wit et al., “Shifting the balance between goals and habits: Five failures in experimental habit induction”, Journal of Experimental Psychology: General 147 (2018).
• W. Wood, J. M. Quinn and D. A. Kashy, “Habits in everyday life”, Journal of Personality and Social Psychology 83 (2002); A. L. Rebar, G. E. Vincent, K. Kovac Le Cornu and B. Gardner, “How habitual is everyday life?”, Psychology & Health (2025).
• P. J. Bayley, J. C. Frascino and L. R. Squire, “Robust habit learning in the absence of awareness and independent of the medial temporal lobe”, Nature 436 (2005); R. Insausti, J. Annese, D. G. Amaral and L. R. Squire, “Human amnesia and the medial temporal lobe illuminated by neuropsychological and neurohistological findings for patient E.P.”, PNAS 110 (2013).
• M. S. Jog, Y. Kubota, C. I. Connolly, V. Hillegaart and A. M. Graybiel, “Building neural representations of habits”, Science 286 (1999).
• K. S. Bate, J. M. Malouff, E. T. Thorsteinsson and N. Bhullar, “The efficacy of habit reversal therapy for tics, habit disorders, and stuttering”, Clinical Psychology Review 31 (2011).
• M. E. Bouton, “Context and behavioral processes in extinction”, Learning & Memory 11 (2004).
• M. Oaten and K. Cheng, “Longitudinal gains in self-regulation from regular physical exercise”, British Journal of Health Psychology 11 (2006); P. Dolan and M. M. Galizzi, “Like ripples on a pond”, Journal of Economic Psychology 47 (2015).
• M. S. Hagger, N. L. D. Chatzisarantis et al., “A multilab preregistered replication of the ego-depletion effect”, Perspectives on Psychological Science (2016); K. D. Vohs et al., “A multisite preregistered paradigmatic test of the ego-depletion effect”, Psychological Science (2021); J. Dang et al., “A multilab replication of the ego depletion effect”, Social Psychological and Personality Science (2020).
• M. Friese, J. Frankenbach, V. Job and D. D. Loschelder, “Does self-control training improve self-control? A meta-analysis”, Perspectives on Psychological Science 12 (2017).
• P. Lally, C. H. M. van Jaarsveld, H. W. W. Potts and J. Wardle, “How are habits formed”, European Journal of Social Psychology 40 (2010).
• C. Duhigg, “How companies learn your secrets”, New York Times Magazine (16 February 2012; archived copy).
• G. Piatetsky, “Did Target really predict a teen’s pregnancy? The inside story”, KDnuggets (7 May 2014), with an excerpt from E. Siegel, Predictive Analytics.
• US Department of the Treasury, “Paul H. O’Neill (2001–2002)”.

Checked October 2026. What we read: the publisher’s excerpt of chapter 1 (part I), the book’s appendix, the author’s Q&A sheet and web pages, his 2012 New York Times Magazine article (via an archived copy), the catalogue record and short search-inside passages of the 2012 Random House edition (not the whole book), and the studies above (abstracts, plus the full texts of the 2002 and 2025 diary studies, the 2006 exercise study and the 2013 paper on E.P.).