Growth factors of the VEGF (vascular endothelial growth factor) family comprises 4 well characterized members that play a crucial role in the biology of blood vessels. They interact with 3 high affinity tyrosine kinase receptors (FLT1/VEGFR1, FLK1/KDR/VEGFR2, FLT4/VEGFR3). VEGF/VEGFR interactions have essential functions in blood vessel formation during development, specific phases of adult life, and in some pathological processes with neo-vascularization such as tumor growth.