The aim of this study was to determine if edema develops in the canine forelimb after relief of prolonged ischemia. Two hours of ischemia was induced either by interrupting brachial artery inflow in collateral-free innervated, naturally and constantly perfused preparations or by applying a pressure cuff in intact preparations. Changes in extravascular fluid volume were inferred from changes in limb weight. Relief of ischemia produced a transient 1.7% increase in weight in the collateral-free, naturally perfused preparation but had no effect on weight in the collateral-free, constantly perfused or intact preparations. Skin lymph flow failed to change significantly and total lymph protein concentration increased only slightly. Thus, relief of 2 hr of ischemia does not produce marked edema or a large increase in microvascular permeability to plasma proteins in the dog forelimb.