The 2009 Angiogenesis Gordon Conference brings together an interdisciplinary group of international scientists to examine state-of-the-art mechanisms of blood vessel formation, growth, regression, alteration in disease, and response to therapy. Use of angiogenesis inhibitors in cancer and eye disease has documented efficacy but has also led to puzzles, paradoxes, and controversies about the mechanism and consequences of their actions. In light of the evolving understanding and expectations, the conference explores the attributes and limitations of current strategies and downstream effects of promoting or blocking angiogenesis in pathological conditions.