Glioblastomas are highly vascularized and, therefore, antiangiogenic agents are increasingly being explored as therapeutic options. This review summarizes the present data on antiangiogenic agents in glioblastoma treatment. The angiogenic pathway in gliomas and the proposed mechanisms of antiangiogenic agents are reviewed briefly, and details of the drugs in clinical trial are provided. In addition to their effects on blood vessels, these agents also have potent antiedema effects that may have therapeutic benefit. The review concludes with a discussion of the role of biomarkers and neuroimaging in the assessment of tumor response. Although preliminary studies of these drugs in glioblastoma have been promising, larger prospective trials that include survival as an end point will be required to determine the ultimate utility of this class of agents. It seems likely that a combination of antiangiogenesis agents with other cytotoxic therapies will be required to achieve maximal efficacy.