This book develops and assesses the criticism that the emphasis on duty in Kant's ethics constitutes a defect. The criticism comprises two objections; that duty plays too large a role in ethics, leaving no room for the supererogatory and that Kant places too much value on acting from duty. Addressing the first objection, part I argues that Kant's distinction between perfect and imperfect duties provides a plausible alternative to contemporary approaches to acts that are said to go "beyond duty". It also tries to locate the underlying disagreements between Kantians and supererogationists and highlights the Kantian picture of character and moral excellence by contrasting it with views implicit in the writings of supererogationists. Addressing...