 But perhaps the most enduring controversies surrounding suicide are philosophical. For philosophers, suicide raises a host of conceptual, moral, and psychological questions. Among these questions are: What makes a person’s behavior suicidal? What motivates such behavior? Is suicide morally permissible, or even morally required in some extraordinary circumstances? Is suicidal behavior rational? Is aiding others to commit suicide morally permissible or even required in some extraordinary circumstances? This article will examine the main currents of historical and contemporary Western philosophical thought surrounding these questions.