The aim of the present work was to study the causes of post-operative recurrences of varicosity and to define approaches to their optimal correction. Duplex scanning (DS) with Color Doppler Imaging of the blood flow was used to examine 126 patients (136 extremities) with recurrences of varicosity. The patients were distributed according to the CEAP clinical classification. Altogether 76 patients (78) extremities with recurrences of varicosity were operated on. 27 persons received different variants of sclerotherapy including echoscleroobliteration. According to the DS data, the most frequently obtained finding in patients with recurrences of varicosity was identification of the perforating veins with valvular insufficiency, namely in 120 (or in 88.2%) extremities. The long stump of the greater saphenous vein (CSV) was discovered in 86 (63.2%) extremities, the long stump of the lesser saphenous vein (LSV) in 6 (4.4%), ectasia of LSV trunk was recognised in 20 (14.5%), incompetence of the valves of the sural veins in 12 (8.8%) extremities. Incompetence of the valves of the deep veins was present in 73 (53.6%) patients. No sources of pathological veno-venous runoff were identified in 12 (8.1%) cases. A good agreement was established between the incidence of valvular incompetence of the deep veins and the disease severity. The indications for surgical correction of valvular insufficiency were worked out. It has been demonstrated that sclero-obliteration is the method of choice in the treatment of the recurrences of varices. The long-term results of operations for recurrences of varicosity were followed up in 62 patients over the period of one to 15 years. Good and satisfactory results were obtained in 60 (96.8%) cases. The authors believe that the majority of varicosity recurrences arise from an inadequate assessment of the status of lower extremity venous bed as well as from technical and methodological faults of the operating surgeon. DS in an indispensable component of preoperative examination of patients with varicosity recurrences.