Many of us are so busy that we might be tempted to think we don't have time to be patient. However, that idea involves a serious underestimation of what patience is and why it matters. In On Patience, Matthew Pianalto revives a richer understanding of what patience is and why it is centrally important in both virtue theory and everyday life. Drawing from a wide range of philosophical and religious sources, Pianalto shows that our contemporary tendency to equate patience with waiting fails to do justice to other aspects of patience such as tolerance, perseverance, and the opposition of patience to anger. With this broader understanding of patience, Pianalto further shows how patience supports the development of other moral strengths, such as courage, justice, love, and hope. In these ways, On Patience sheds light on Franz Kafka's remark that, "Patience is the master key to every situation," and Gregory the Great's perhaps surprising claim that, "Patience is the root and guardian of all the virtues." This first book-length contemporary philosophical examination of patience will be of interest to students and scholars not just of virtue ethics, but also of moral philosophy more broadly.