Background:The endothelium requires stabilization factors for efficient blood vessel formation. Results: Engulfment and cell motility 1/dedicator of cytokinesis 180 (Elmo1/Dock180) expression reduces endothelial cell apoptosis in vitro and in vivo. Conclusion: Elmo1/Dock180 protects endothelial cells from apoptosis and acts as a stabilization factor for the endothelium. Significance: First report revealing a cell-intrinsic, pro-survival function of Elmo1/Dock180 in the endothelium.