Although it has a long and rich history, HRD has emerged only recently as a distinct discipline and field of practice. This book provides an review and synthesis of how many fields (psychology, economics, systems theory, and others) have contributed to the development of HRD. In so doing it details how these fields, along with a growing body of research, have contributed to the development of the theoretical and philosophical foundations and HRDs emergence as a unique discipline. This is not a quick "how-to" book but rather a scholarly examination of the core beliefs, values, worldview, and principles that are the framework for HRD. It will be of primary interest to academics, scholars, and researchers. It also offers reflective practitioners the opportunity to re-examine the beliefs, values, and approaches that guide their work. The book is logically organized, well written, and replete with diagrams, models, and graphics that illustrate and clarify key concepts. Sure to become a classic text and reference, I highly recommend it to anyone who seeks to develop a deeper understanding of Human Resource Development.