Think Small

What if the secret to achieving your biggest life goals wasn’t about aiming higher, but about thinking smaller? In Think Small, Owain Service and Rory Gallagher—leaders of the UK’s influential Behavioural Insights Team (the “Nudge Unit”)—reveal a framework for turning ambitions into action, rooted in psychology and behavioral economics. Drawing from years of experimentation across public policy and personal development, they argue that massive goals are rarely achieved through massive action. Instead, progress happens when you create smart systems, simple habits, and small, consistent steps that keep you moving in the right direction.

The book’s foundation lies in the understanding of how human decision-making works. As Nobel laureate Daniel Kahneman explained in Thinking, Fast and Slow, we operate with two mental systems: a slow, reflective system and a fast, automatic one. We often assume our rational, deliberate mind is in charge, but our fast system drives most of our daily behavior — for better or worse. This means that even well-intentioned goals (“I’ll exercise more, spend less, or be more patient”) often fail because they rely on willpower and memory instead of small structural changes that align our environment with our intentions.

The Seven-Step Framework

Service and Gallagher organize the book around a practical seven-step sequence designed to act as behavioral scaffolding: Set, Plan, Commit, Reward, Share, Feedback, and Stick. These steps aren’t just motivational slogans—they’re empirically tested behavioral tools drawn from hundreds of real-world experiments. Each step focuses on aligning human psychology with realistic goal execution. For instance, Set helps you choose a goal that genuinely improves wellbeing, Plan ensures you create simple action rules, Reward helps sustain motivation, and Share leverages social networks for accountability and success.

Why Thinking Small Works

The authors’ central argument challenges traditional self-help approaches that focus on “dreaming big” and “thinking positive.” As they explain through the story of Sarah, a struggling student who went from failing math to rediscovering motivation by learning to break her goal into small, manageable chunks, thinking small is the art of turning ambition into process. This approach reduces the friction between intention and action by exploiting what the authors call “behavioral bottlenecks” — moments where human habit, bias, or fatigue derail progress. With concrete examples from education, health, and business, they show how small behavioral tweaks — like simplifying plans, forming public commitments, or structuring feedback — can generate compounding effects over time.

From Policy Insights to Personal Growth

Although the Behavioral Insights Team originally used these concepts to improve public services—such as redesigning tax reminders or helping job seekers find work—Think Small translates the same science into tools for individuals. Whether you want to lose weight, save money, get fitter, or nurture better relationships, behavioral insights can help you nudge yourself toward success. The authors frame their ideas as “self-nudges”: small, strategic interventions that reshape your environment so that the easy choice becomes the right choice. For example, rather than relying on self-discipline to eat well, you can remove unhealthy snacks from view (“make it easy”); instead of vague goals like “save more,” setting automatic transfers turns intention into behavior.

The Power of Behavioral Scaffolding

David Halpern, the Behavioral Insights Team’s chief executive, opens the book with a vivid metaphor for how people build good habits: achieving a goal is like constructing a building—it needs solid foundations, structured scaffolding, and small, careful adjustments over time. Through behavioral scaffolding, you support yourself when your focus wavers, reducing the need for constant self-control. The scaffolding eventually becomes invisible, but your behaviors stand tall on their own.

Throughout the book, Service and Gallagher demonstrate how applied common sense—reinforced by behavioral evidence—can vastly increase your chances of success. Each chapter offers real examples (a teacher improving class results, a smoker quitting through commitment contracts, an athlete enhancing performance through chunking practice) to illustrate that effective change doesn’t come from trying harder but from designing smarter. Think Small is ultimately a handbook for turning lofty aspirations into daily behaviors that stick. It reminds readers that the difference between big dreams and lasting results is often found in the smallest, smartest details.

Most of us have long lists of goals—get fit, improve work-life balance, earn more money—but few of them ever stick. The first step in Think Small is learning to set the right goal. The authors begin by emphasizing that meaningful goals must improve wellbeing, not just status or possessions. Drawing on research by psychologists like Martin Seligman and economists like Richard Layard, they explain that people often misjudge what actually makes them happy. Money, for example, only increases happiness up to a point; beyond that, relationships, health, learning, and purpose do far more to sustain wellbeing.

Align Goals with Wellbeing

Service and Gallagher propose five happiness-enhancing goal categories: strengthening relationships, getting healthy, learning new things, being curious, and giving to others. They point to research showing that prosocial spending (spending on others) and volunteering make people significantly happier than self-focused consumption. In one study by Elizabeth Dunn and colleagues, people given $20 to spend on someone else reported greater happiness than those who spent the money on themselves. The authors even apply this logic internally at the Behavioral Insights Team—half of team bonuses must be spent on colleagues who contributed to the winner’s success.

Focus on One Goal

The second rule is about focus: don’t dilute your effort across ten resolutions. Behavioral economics shows that multiple competing goals overload cognitive bandwidth—the limited mental energy we have for decision-making. A fascinating savings study in India by Dilip Soman and Min Zhao found that participants who pursued a single savings goal saved twice as much as those who had multiple competing ones. The same principle applies across domains: pick one goal that excites you and that you’ll sustain through difficulty.

Make It Concrete and Time-Bound

Good goals are not abstract hopes (“I want to be healthier”) but measurable, time-bound commitments (“I will run a half marathon by May”). The authors draw on Edwin Locke’s goal-setting theory, which found that specific and challenging goals produce better performance than vague or easy ones. A study at MIT showed that students who set self-imposed deadlines for writing essays outperformed those who left all submissions to the end of term—the self-imposed constraints mimicked the “expiration bump” of real deadlines. Similarly, adding a firm date to your personal goal increases the pressure to act.

The Set stage, then, is about clarity and alignment. You identify what truly improves your wellbeing, choose a single, motivating objective, and fix clear targets and deadlines. The authors’ message is simple but profound: aiming at everything ensures achievement in nothing; aiming small but true ensures progress that matters.

Once your goal is chosen, the next challenge is planning. Why do so many good intentions vanish between decision and action? The authors argue that the problem is “cognitive friction”: plans are too complex, abstract, or weakly tethered to routine life. In Think Small, planning means making goal pursuit almost effortless by using bright lines, implementation intentions, and habit loops.

Keep It Simple—The Power of Bright Lines

Owain Service shares his personal experiment: to reduce evening drinking, he set a bright-line rule—no alcohol at home during the week. This unambiguous rule eliminated fuzzy mental effort (“Am I still within three units?”). Such rules remove the daily negotiations with yourself. Psychologist Rory Sutherland calls these simple boundaries “bright lines,” similar to age-old religious practices like Sabbath observance: easy to understand, hard to misinterpret. The overall principle—make actions easy and frictions high for unwanted behaviors—is foundational to behavioral design (a logic echoed by James Clear’s Atomic Habits).

Turn Intentions into Implementation Plans

Psychologist Peter Gollwitzer discovered that linking intentions to real-world cues—when, where, and how—makes them far more likely to happen. For example, people who specified “I will vote at 7 a.m. after breakfast” were 9% likelier to vote than those who just intended to. Similarly, Wharton professor Katy Milkman found that writing down vaccination times increased flu shot attendance by 13%. These “if-then” plans automate decision-making, capitalizing on predictable moments you can anchor habits to (“If I get home, then I’ll put on my running shoes”).

Habit Formation: From Slow to Automatic

To sustain change, your plan must evolve into autopilot. Habits form through repeated pairing of cues and actions until behavior triggers automatically. The authors highlight ingenious studies: Vietnam veterans who stopped using opiates permanently after leaving war zones (cues removed) and moviegoers who unconsciously ate stale popcorn simply because they were at a cinema (cue triggered habit). To build good habits, repeat positive actions in consistent contexts for at least two months, making the cues obvious and the effort minimal.

Through simplification, contextual linking, and repetition, Plan ensures that following through on your goal becomes almost instinctive. As the authors emphasize, the best plans are not intricate spreadsheets—they’re the routines embedded seamlessly into daily life.

We often believe motivation alone will sustain us, but human behavior is frail against procrastination and temptation. That’s why commitment devices—external or social contracts that bind your future self—are so powerful. The Commit chapter teaches three ways to lock yourself in: make a pledge, make it public, and appoint a referee.

Binding Your Future Self

Behavioral economists Daniel Read and George Loewenstein showed that we have two selves: the present self (wants Netflix and dessert) and the future self (wants fitness and discipline). By pre-committing—choosing today for tomorrow—you force alignment. Rory Gallagher exemplified this when he wrote on his office whiteboard, “I will go to the gym twice a week for three months,” accompanied by a painful penalty: if he failed, he’d wear the jersey of rival football team Arsenal. The public pledge and embarrassment potential transformed wishful thinking into compliance.

The Power of Public Promises

Writing a goal down and making it public dramatically increases follow-through. Social psychology backs this up: Solomon Asch’s conformity experiments showed that public statements create powerful consistency pressures. Similarly, beachgoers who agreed to “watch a stranger’s radio” chased potential thieves 95% of the time—commitment transformed obligation into identity. The authors liken this to why marriage vows are made publicly: announcing our promises locks them socially. Research even suggests larger weddings correlate with lower divorce rates, probably due to community reinforcement.

Choose a Commitment Referee

Dean Karlan and Ian Ayres’ site stickK.com formalized this concept. Users who chose a referee to verify success were 70% more likely to meet their goals. A good referee is firm but fair—not a lenient partner or a vindictive rival. The Behavioral Insights Team applied this logic in job centers: participants set personal job search goals, signed plans, and were held accountable by advisors acting as referees. The results: higher job finding rates and stronger motivation.

Commitment transforms your environment into an ally rather than an enemy. In a world of frictionless temptation, externalizing your promises makes success the path of least resistance.

Incentives drive behavior—but only when designed carefully. In Think Small, rewards are not simple bribes; they are psychological tools that reinforce progress. The authors show that the key is in the details: how rewards are structured, framed, and timed determines whether they motivate or backfire.

Put Something Meaningful at Stake

Dean Karlan’s smoking cessation study in the Philippines (