This volume "Angiogenesis in Brain Tumors" is part of the book series "Cancer Treatment and Research" and offers a detailed overview of the biology of angiogenesis in the central nervous system, the role of angiogenesis in brain tumor development and growth, and anti-angiogenic therapeutic applications. Our understanding of the mutual relationship between tumor growth and concomitant neovascularization has provided important insights into the biology of brain tumors and contributed to the development of new treatment strategies. Many of the early experimental findings on angiogenesis were made using brain tumor models. This was largely due to the fact that brain tumors are among the highest vascularized tumors. In addition, until to date all efforts to develop efficient therapies for these highly malignant tumors have met with little if any success . The scientific evidence on the role of angiogenesis in tumor development accumulated until today has already let to the initiation of several clinical trials. Despite the fact that not all expectations have been fulfilled, the results available so far are promising and suggest that anti­ angiogenic therapeutic strategies may be of benefit to our brain tumor patients in the near future. The volume is comprised of four sections . The first section is dedicated to the principles of angiogenesis in the central nervous system and gives an overview on the cellular, physiological and developmental processes of angiogenesis.