In recent years, our understanding of B-cell biology and the roles of B cells in normal immune responses and autoimmunity has increased dramatically. We no longer think of B cells simply as antibody factories. It is clear that these diverse and exquisitely regulated cells may contribute in a multitude of ways to immune responses. Animal models, clinical trials of biologic agents, and the ever expanding field of molecular biology have made great contributions to our current knowledge. With this improved understanding, we are afforded the opportunity to consider numerous potential therapeutic targets for treating autoimmune disease. As this growing science evolves, we can expect to see the advent of new therapies and new hope for patients who are afflicted with these disorders.