OBJECTIVE To compare the outcome of a modified one-layer and two-layer vasovasotomy (VV) in two groups of similar men undergoing vasectomy reversal. PATIENTS AND METHODS The charts and surgical records of all surgical procedures performed on men undergoing a modified one- or two-layer VV between June 1992 and July 1994 were retrospectively reviewed. A successful outcome (patency) was defined as sperm present at follow-up (mean follow-up 8 weeks). A modified one-layer VV was used in 17 men (group 1) and a two-layer VV in 23 (group 2). RESULTS Sperm were present in both groups if surgery was undertaken after vasal obstruction lasting < 36 months. The modified one- and two-layer VV had equal patency (88% and 90%, respectively) when undertaken after an obstructed interval of 36-96 months; outcomes were poorer if surgery was performed after > 96 months. The mean operative duration was 96 min for a modified one-layer VV and 167 min for the two-layer VV. CONCLUSIONS The simpler and faster modified one-layer VV provides sufficient accuracy for successful vasectomy reversal in most cases. For most patients, both procedures have equivalent patency.