Utilitarianism began as a movement for social reform that changed the world, based on the ideal of maximizing pleasure and minimizing pain. There is a tendency to enter into debates for and against the ethical doctrine of Utilitarianism without a clear understanding of its basic concepts. The Pursuit of Happiness now offers a rigorous account of the foundations of Utilitarianism, and vividly sets out possible ways forward for its future development. To understand Utilitarianism, we must understand utility: how is it to be measured, and how the aggregate utility of a group can be understood. Louis Narens and Brian Skyrms, respectively a cognitive scientist and a philosopher, pursue these questions by adopting both formal and historical methods, examining theories of measuring utility from Jeremy Bentham, the founder of the Utilitarian movement, to the present day, taking in psychophysics, positivism, measurement theory, meaningfulness, neuropsychology, representation theorems, and the dynamics of formation of conventions. On this basis, Narens and Skyrms argue that a meaningful form of Utilitarianism that can coordinate action in social groups is possible through interpersonal comparison and the formation of conventions.