The selections not only include St. Thomas Aquinas’s views on government, law, war, property, and sexual ethics, but also provide the theological, epistemological, and psychological background for his political and ethical thought, including the Five Proofs on the existence of God and Aquinas’s theories of knowledge, the soul, the purpose of man, and the order of the universe. Throughout the book, footnotes explain technical terms and historical, biblical, and classical references.

"Backgrounds and Sources" follows the text, with selections from the writings of Aristotle, St. Augustine, and Dionysius the Areopagite.

"Interpretations" traces Aquinas’s influence on medieval thought, on Roman Catholicism during the Renaissance, on early modern political thought (Richard Hooker and Francisco Suarez), on nineteenth-and twentieth-century papal social thought, and on contemporary Christian Democratic political parties in Europe and Latin America.

The volume concludes with "Contemporary Problems in Thomistic Ethics", which contains eight analyses of the influence of Aquinas's thought on modern debates on war, contraception, and abortion.

A Selected Bibliography is included.