The author first argues that Kant's distinction between perfect and imperfect duties provides a plausible and intriguing alternative to contemporary approaches to charity, self-sacrifice, heroism, and saintliness. She probes the differences between the supererogationist and the Kantian, exploring the motivation between the former's position and bringing to light sharply divided views on the nature of moral constraint and excellence. Baron then confronts problems associated with Kant's account of moral motivation, she argues that the value that Kant attaches to acting from duty attaches primarily to governing ones conduct by a commitment to doing what morality asks. Thus understood, Kant's ethics steers clear of the most serious criticism. Of special interest is her discussion of overdetermination. Clearly written and cogently argued, takes on the most philosophically intriguing challenges to Kantian ethics and subjects them to a rigorous yet sympathetic assessment. Readers will find here original contributions to the debate over impartial morality.