The American Urological Association Prostate Guideline Update Panel was charged with updating the Guidelines for Clinically Localized Prostate Cancer. In assessing outcomes with treatment, it became apparent that a highly variable number of definitions exist with respect to biochemical recurrence. Herein, we review the variability in published definitions of biochemical recurrence and make recommendations directed toward improving this terminology by recommending a standard definition in patients treated with radical prostatectomy.