Data collected during the past years indicate that AJ- and more specifically VE-cadherin play an important role in endothelial cell biology. VE-cadherin may transfer information intracellularly through interaction with a complex network of cytoskeletal and signaling molecules. Expression of VE-cadherin is required for the control of vascular permeability and vascular integrity. In addition, the molecule may exert a morphogenetic role modulating the capacity of endothelial cells to organize into tubular-like structures. VE-cadherin presents many structural and sequence homologies to the other members of the family and apparently binds to the same intracellular molecules. However, remarkably, VE-cadherin may transfer specific signals to endothelial cells to modulate their functional reactivity.