his book is devoted to vascular endothelial growth factor A (VEGF his book is devoted to vascular endothelial growth factor A (VEGF or VEGFA), a secreted signalling protein of great significance for or VEGFA), a secreted signalling protein of great significance for T development and disease in vertebrates. VEGFAcontrols the prolif Tdevelopment and disease in vertebrates. VEGFA controls the prol- eration, eration, migration migration, , specialisatio specialisation n and and surviva survival l of vascula ofvascular r endothelia endothelial l cells, cells, and and iit t isis therefor therefore e essentia essential l for th for e establishmen the establishment t of a functiona ofa functional l blood vesse blood l vessel circuit. circuit. IIn n addition addition, , VEGF VEGFA A is emergin is emerging g as a versatil as a versatile e patternin patterning g factor fofactor r for several several non endothelia non-endothelial l celcell l type types s in vertebrates in vertebrates. . ThusThus, , it playit s a centra plays al rol central e role during organ development at multiple levels, including blood vessel growth, duringorgan developmentat multiple levels, including blood vessel growth, vessel-mediated vessel mediated orga organ n inductio induction n andand tissutissue e differentiation differentiation. . The The discover discovery y ofof non endothelia non-endothelial l rolesroles for VEGF for VEGFA A initiallinitially y came ascarne a as a surprise. surprise.