The effects of nerve sparing on the risk of positive surgical margins (PSMs) and biochemical recurrence after radical prostatectomy (RP) remain controversial. We examined data from 1018 men treated by RP between 1988 and 2006 at five centers in the Shared Equal Access Regional Cancer Hospital database. Neither bilateral nor unilateral nerve-sparing techniques were associated with a higher risk of PSM; on multivariate analysis of individual sides, the risk of PSM on either side was not increased by nerve sparing on either side. The risk for biochemical recurrence was not affected by bilateral or unilateral nerve sparing. When used on appropriately selected patients, nerve sparing does not increase the probability of PSM or biochemical recurrence after RP.