Social trust, often referred to as “generalized” trust, is trust in strangers—persons within one's society with whom one has little personal familiarity. The volume begins with “Legal and Social Trust in Africa,” which uses survey data to explore the relationship between social trust and trust in the legal system. However, it is better to understand social trust as trust that people share and recognize an array of social rules that do not necessarily correspond to what persons consider of ultimate value in life. The present volume is divided into three parts: empirical research on social trust, concepts of social trust, and the ethics and politics of social trust. This essay introduces readers to debates about how trust as a general concept is defined, which will have implications for how social trust should be conceptually defined.