Utilitarianism is a classic work of ethical theory, arguably the most persuasive and comprehensible presentation of this widely influential position. Mill argues that it is pleasure and pain that ought to guide our decision-making&and not the pleasure and pain of any one person or group, but the summative experience of all who are affected by our actions. While he didn’t invent utilitarianism, Mill offered its clearest expression and strongest defense, and expanded the theory to account for the variety in quality that we find among specific pleasures and pains. Today, Mill’s version of the “Greatest Happiness Principle” is a standard premise in many moral arguments within the academy and in practical ethical and political deliberation. The complete text of the 1871 edition of Utilitarianism is presented here, with footnote annotations added to clarify unfamiliar references and terminology for the student reader. A detailed introduction by the editor is divided into brief digestible parts discussing the context of the text and offering guidelines on how to read it accurately and critically. This edition has its origin in the acclaimed Broadview Anthology of Social and Political Thought and adheres to the anthology’s format and high standard of accuracy and accessibility.