Leukocyte transendothelial migration is controlled by chemokine-induced signalling in leukocytes and integrin-ligand-induced bidirectional signalling in both leukocytes and endothelial cells. It is now generally accepted that endothelial signalling following leukocyte adhesion, serves to facilitate the crossing of the endothelium, be it via the paracellular or transcellular route. This brief overview discusses the main findings within this area and highlights some recent findings that shed new light on adhesion-induced signalling in the context of leukocyte transendothelial migration.