Groups of people are commonly said to be collectively responsible for what has happened. Sometimes the groups claimed to be responsible are vast in size, as when collective responsibility is ascribed to the class of all Americans or the class of all white males. In this book the concept of collective responsibility is analyzed. It is examined not only in the light of what philosophical proponents (such as Cooper, Held, Bates, French, Swinburne, and May) have said about it, but a genuine attempt is made to make sense of what ordinary people say about responsibility when it is ascribed to groups of people. Accordingly, it is distinguished from related concepts such as shared responsibility and moral taint. Parallels are examined between the actions of an individual and the actions of a group or collective, parallels which seem to make ascriptions of collective responsibility more plausible. Some philosophers oppose collective responsibility and argue for an individualist type of position; in this regard the positions of Lewis and Sverdlik are critically examined. The final chapter contains the author's own position, a position which affirms that collective responsibility is possible but which also preserves some of the central intuitions of the individualist.