This book focuses on the development of psychological self-understanding, healing psychologically painful inner conflicts, and the basis of psychological and spiritual fulfillment. Readers will discover a new understanding of effective psychotherapy, groundbreaking diagnostic psychological testing research, and the distinction between the ego self-concept, the experiential self, and the transpersonal self (the real self, the relational self, or the holistic self). It also clarifies aspects of optimal psychological health, such as authenticity, sincerity, integrity, creativity, intuition, empathy, courage, strength of character, inspiration, unselfish love (or warmhearted caring), emotional security, inner wholeness, vitality, and fulfillment. Principles of psychological healing and self-transformation can enhance the development of interpersonal relationships, as well as facilitate effective and fulfilling ways of living in society. The authors deeply explored their own psychological pain and experiential truth to write this book, so readers can achieve greater self-understanding, fulfillment, and liberation from psychological pain.