Tumor ablation methods using chemicals, radiation, photodynamic therapy, cryoablation, high-temperature, radiofrequency, high intensity focused ultrasound, and electric-based ablation have been developed for focal tumors. In this book experts will deal with two main topics: I. What are the principles of the various ablation modalities, and II. How each method affects the tumor cells and their microenvironment, and how these effects are responsible for the induction of specific anti-tumor immunity. The aims of this book are thus: 1. Familiarize the readers with various methods of in situ tumor ablation. 2. Review the literature and stimulate comparisons on the efficacy of different ablation methods for the treatment of tumors of different histotypes. 3. Review the literature on the effects of various ablation methods on systemic and local anti tumor immunity and on other manifestations of the interactions of tumors with their microenvironment. 4. Stimulate comparative studies on the immunostimulatory effects of different ablation modalities.