Interest in angiogenesis research remains strong in recent years and exciting new discoveries, about modulators of angiogenesis, their receptors, the transduction mechanisms and the angiogenic genes involved, have contributed to our present day understanding of this complex process. This knowledge has provided the basis and broadened the scope of angiogenesis - based therapy in oncology and many other clinical conditions. This monograph contains the contributions to the NATO Advanced Study Institute on "Angiogenesis: Models, Modulators and Clinical Applications", which was held in Rhodes, Greece, from June 20-30, 1997. This was the fourth of a series of NATO supported international meetings on Angiogenesis aiming to bring together basic scientists with clinicians to exchange ideas, disseminate new knowledge and discuss the present status and potential new directions in this fast moving area of biomedical research. The International Organising Committee that included Drs. E. Dejana, C Haudenschild, M. Hackel, H. Kleinman, P. Lelkes, M. Presta, P. Polverini, D. Thompson, has provided invaluable help with their insightful suggestions in the formulation of the scientific program for which I am grateful. I wish to thank all the participants for their enthusiastic participation and their complimentary comments on the success of the conference.