Disclosed are compositions and methods useful for targeting tissue undergoing angiogenesis or to cells or tissue expressing &alpha；v integrins. The compositions and methods are based on peptide sequences that selectively bind to and home to tissue undergoing angiogenesis or to cells or tissue expressing &alpha；v integrins in animals. The disclosed targeting is useful for delivering therapeutic and detectable agents to tissue experiencing angiogenesis or to cells or tissue expressing &alpha；v integrins.
