['Proteinuria is associated with endothelial dysfunction (ED) and increased mortality. We investigated whether urinary protein excretion (UPE) is correlated with markers of ED and whether these markers affect the association of proteinuria with mortality in renal transplant recipients (RTR).', 'Six hundred four RTR with a functioning graft for more than 1 year were included. RTR were divided according to UPE: less than 0.3, 0.3 to 1.0, and more than 1.0 g/24 hr. Soluble intercellular adhesion molecule type 1 (sICAM-1) and soluble vascular cellular adhesion molecule type 1 (sVCAM-1) were measured using ELISA.', 'UPE (0.2 [0.0-0.5] g/24 hr), sICAM-1 (603 (514-721) ng/mL), and sVCAM-1 (952 [769-1196] ng/mL) were measured at 6.0 (2.6-11.4) years posttransplant. During follow-up for 5.3 (4.7-5.7) years, 94 (16%) RTR died. UPE was correlated with sVCAM-1 (standardized beta=0.13, P=0.001) but not with sICAM-1 (standardized beta=0.04, P=0.3). RTR with UPE more than 1.0 g/24 hr and high sICAM-1 (hazard ratio=4.7, 95% confidence interval 2.3-9.7, P<0.0001) or sVCAM-1 (hazard ratio=4.2, 95% confidence interval 2.0-8.6, P=0.0001) concentrations were at increased risk for death, whereas RTR with UPE more than 1.0 g/24 hr and low concentrations of sICAM-1 and sVCAM-1 were not.'] Do circulating markers of endothelial dysfunction interact with proteinuria in predicting mortality in renal transplant recipients?