This book deals with the paradoxical role of autophagy in tumor suppression and tumor promotion in cancer cells. Autophagy plays opposing, context-dependent roles in tumors; accordingly, strategies based on inhibiting or stimulating autophagy could offer as potential cancer therapies. The book elucidates the physiological role of autophagy in modulating cancer metastasis, which is the primary cause of cancer-associated mortality. Further, it reviews its role in the differentiation, development, and activation of multiple immune cells, and its potential applications in tumor immunotherapy. In addition, it examines the effect of epigenetic modifications of autophagy-associated genes in regulating tumor growth and therapeutic response and summarizes autophagy’s role in the development of resistance to a variety of anti-cancer drugs in cancer cells. In closing, it assesses autophagy as a potential therapeutic target for cancer treatment. Given its scope, the book offers avaluable asset for all oncologists and researchers who wish to understand the potential role of autophagy in tumor biology.