Pretty much all the advice about happiness we have heard revolves around one basic assumption: that we can think ourselves happier. But in this book, behavior and happiness expert Paul Dolan reveals that the key to being happy does not lie in changing how we think--it's changing what we do. This is not just another happiness book. This book combines the latest insights from economics and psychology to illustrate that in order to be happy we must behave happy Our happiness is experiences of both pleasure and purpose over time and it depends on what we actually pay attention to. Using what Dolan calls deciding, designing, and doing, we can overcome the biases that make us miserable and redesign our environments to make it easier to experience happiness, fulfilment, and even health. With uncanny wit and keen perception, Dolan reveals what we can do to find our unique optimal balance of pleasure and purpose, offering practical advice on how to organize our lives in happiness-promoting ways and fresh insights into how we feel, including why: - Having kids reduces pleasure but gives us a massive dose of purpose - Gaining weight won't necessarily make us unhappier, but being too ambitious might - A quiet neighborhood is more important than a big house Vividly rendering intriguing research and lively anecdotal evidence, this book offers an absorbing, thought-provoking, new paradigm for readers.