The field of hospital medicine continues to grow rapidly, and with this growth has come the realization that residency alone may not provide the full complement of skills required of a successful hospitalist. As a result, several institutions have started hospitalist fellowships, new programs with the specific goal of training clinicians to improve hospital care. These fellowships offer diverse approaches to preparation for a hospitalist career, with opportunities for advanced training in clinical care, teaching, research, and quality improvement. This article provides an overview of the programs, explores the choices for trainees in selecting a fellowship, and the challenges for institutions in developing a new fellowship. Although hospitalist fellowships are still in evolution, they will play an important role in the development of hospital medicine.