All humans laugh. However, there is little agreement about what is appropriate to laugh at. While laughter can unite people by showing how they share values and perspectives, it is also has the power to separate and divide. Humor that "crosses the line" can make people feel excluded and humiliated. This collection of new essays addresses possible ways that moral and ethical lines can be drawn around humor and laughter. What would a Kantian approach to humor look like? Do games create a safe space for profanity and offense? Contributors to this volume work to establish and explain guidelines for thinking about the moral questions that arise when humor and laughter intersect with medicine, gender, race, and politics. Drawing from the work of stand-up comedians, television shows, and ethicists, this volume asserts that we are never just joking.