In keeping with the aim of The Nonprofit Human Resource Management Handbook to connect research to practice, this introductory chapter focuses on nonprofit theories of particular interest to the study and practice of nonprofit human resource management (HRM). Each chapter author in this book will have made his or her own choices about the conceptual landscape considered worthy of coverage. As a consequence, we may vary in the groundwork we cover, but that strategy overall should be considered an exciting rather than confusing aspect of nonprofit HRM study and practice, since all chapter authors would agree that this field of research and practice is still in development and moving in rapid and sometimes unexpected directions.