Psycho-Oncology, 4th edition, follows the publication of Psycho-Oncology, 3rd edition in 2015. This is the latest in the series of textbooks which have defined the field of psycho-oncology. William Breitbart, MD, serves as the new senior editor along with associate editors Phyllis N. Butow, PhD, MPH, of the University of Sydney; Paul B. Jacobsen, PhD, of the U.S. National Cancer Institute; Wendy W. T. Lam, RN, PhD, of the University of Hong Kong; Mark Lazenby, APRN, PhD, of the University of Connecticut School of Nursing; and Matthew J. Loscalzo, MSW, of the City of Hope. In this 4th edition of Psycho-Oncology, we feel we have accomplished the delicate task of having this “Official Textbook of our Field” serve both as the source textbook providing the broadest and most multidisciplinary essential science and practice of the field of psycho-oncology, as well as the newest and latest innovations and cutting-edge research and clinical practice that would equip our readers with the knowledge and resources to participate in the “new frontiers of psycho-oncology.” Several new sections and areas of update include: 1. Evidence-Based Interventions; 2. Digital Health Intervention; 3. Biobehavioral Psycho-Oncology; 4. Geriatric Oncology; 5. Pediatric Psycho-Oncology; 6. Survivorship; 7. Palliative Care and Advanced Planning; 8. Diversities in the Experience of Cancer; 9. Behavioral and Psychological Factors in Cancer Risk; Screening for Cancer in Normal and At-Risk Populations; 10. Screening and Testing for Germ Line and Somatic Mutations; 11. Screening and Assessment in Psychosocial Oncology; 12. Building Supportive Care Teams; 13. Psycho-Oncology in Health Policy.