The records of 122 patients who underwent Doppler evaluation for the postphlebitic syndrome were reviewed to determine the relationship between location of venous valvular incompetence and severity of clinical signs. Categorized according to the most severe physical finding, there were 35 limbs with perimalleolar ulcers, 113 with stasis pigmentation, 26 with swelling, and 70 with no overt signs. Incompetent veins, either deep or superficial, were present in 93% of the symptomatic and 59% of the asymptomatic limbs. Proximal (iliofemoral) deep venous incompetence was not strongly correlated with disease severity (p less than 0.10), but distal (popliteotibial) deep venous and superficial venous incompetence were (both, p less than 0.0005). The relative frequency of isolated proximal incompetence appeared to diminish with increasing disease severity; whereas that of distal incompetence, with or without associated proximal venous incompetence, increased. Isolated proximal venous incompetence was found in only 5% of limbs with severe disease (ulcers or pigmentation). In limbs with severe signs, distal venous incompetence was present in 67% of those with proximal venous incompetence and in 57% of those in which the proximal valves were competent. These findings cast doubt on the potential value of proximal venous valvular reconstruction, especially in limbs with combined proximal and distal insufficiency.