Edema of the foot and leg incident to successful arterial surgery was evaluated in 137 arterial reconstructions on the lower extremity. Both the postoperative hyperemia and the edema appeared to be directly related to the degree of pre-existent ischemia. When employed, heparin or dextran or both were effective in preventing postoperative phlebitis but did not alter the postoperative hyperemia and edema. Furthermore, phlebograms and pressure studies obtained in edematous extremities disclosed normal venous morphology and hemodynamics. The underlying mechanism for this edema is believed to be the sudden re-establishment of high pressure in an atrophic arterial tree previously exposed to a reduced intravascular pressure of long duration. This effects overstretching of the arterial bed and a remarkable increase in capillary filtration. A significant secondary factor is the compromised venous return incident to muscular atrophy and limited joint movements that are prevalent in ischemic limbs.