Prior to the description of the anatomic nerve sparing radical prostatectomy, most men were rendered impotent following radical perineal or retropubic prostatectomies. The fact that these "erection" nerves were localized outside the prostate suggested the feasibility of totally eradicating localized prostate cancer with preservation of erectile function in selected cases. All of these studies collectively suggest that unilateral excision of neurovascular bundles will compromise potency rates in between 15% to 20% of cases. It seems logical to report the risk of extracapsular extension independently for the two sides of the prostate, especially since independent decisions are made relative to the nerve sparing status of the different sides. Extracapsular extension is a risk factor for positive surgical margins. Positive surgical margins represent an independent risk factor for biochemical recurrence following radical prostatectomy. The surgeon is left with the dilemma of whether to maximize potency at the risk of compromising cancer control. In cases with a 30% risk of side specific extracapsular extension, using the above assumption, the risk of developing a positive surgical margin and biochemical recurrence is only 4.7% and 2%, respectively.