Truth commissions have become one of, if not the most utilized mechanisms for addressing past human rights abuses in transitional societies. This chapter critically examines the role and challenges of truth commissions as a major mechanism for dealing with past atrocities. It provides a brief historical account of truth commissions before setting out the features and functions of the mechanism. The chapter sets out the challenges to the work of truth commissions. The chapter concludes on the note that truth commissions have become a choice mechanism of transitional justice despite the challenges of their use in attempts to abate impunity and secure justice for victims of gross violations of human rights. It provides a brief examination of the truth and reconciliation process in South Africa, Sierra Leone, Nigeria and Canada to highlight the differing contexts in which truth commissions have been established.