The present invention provides methods for reducing or inhibiting angiogenesis in a tissue, by contacting α5β1 integrin in the tissue with an agent that interferes with specific binding of the α5β1 integrin to a ligand expressed in the tissue. The invention further provides methods of reducing or inhibiting angiogenesis in a tissue in an individual, by administering to the individual an agent that interferes with the specific binding of α5β1 integrin to a ligand expressed in the tissue; and methods of reducing the severity of a pathological condition associated with angiogenesis in an individual, by administering to the individual an agent that interferes with specific binding of α5β1 integrin to a ligand in a tissue associated with the pathological condition.