This rich and provocative study assesses Herbert Spencer's pivotal contribution to the emergence of liberal utilitarianism and shows that Spencer, as much as J. S. Mill, provided liberal utilitarianism with its formative contours. Like Mill, Spencer tried to reconcile a principle of liberty and strong moral rights with a utilitarian, maximizing theory of good. In this powerful and sympathetic account, David Weinstein argues that Spencer's moral and political thought exhibits greater systematic integrity than received views of his thought acknowledge. However, Weinstein also examines the problems and flaws in Spencer's version of liberal utilitarianism, and shows that, precisely because of these flaws, it is engaging and deserving of our critical attention. This challenging study will be of interest to graduates and scholars in the fields of political theory, moral and political philosophy, and the history of political thought.