Functional genomic and proteomic approaches have begun to revolutionize cancer research. The advent of powerful technologies, such as DNA microarrays, serial analysis of gene expression, RNA interference and proteomics, has accelerated investigations of gene identification and function at a scale never before accomplished. Approaches integrating these technologies with high-throughput forward and reverse genetic screens, are already providing insights into the mechanistic understanding of angiogenesis, leading to the identification of proteins that can be used for selective targeting of tumor vessels.