The goal of identifying a set of pretreatment risk-stratifying factors for patients with localized prostate cancer is to be able to individualize treatment and optimize patient selection for clinical trials. Low-risk patients are most likely to remain disease-free following local therapy, whereas high-risk patients are not. By identifying a high-risk group in which approximately two-thirds of the patients fail biochemically within 10 years following local therapy, the ability to detect a difference in outcome as a result of additional therapy (if any difference exists) is maximized. Specifically, small improvements in outcome associated with the use of novel therapies can be measured more quickly in the high-risk population because of the intrinsically higher failure and progression rates. Therefore, novel therapies should be studied first in high-risk populations using a prospective randomized trial design (ie, local therapy with or without novel therapy). If efficacy is established in the high-risk cohort, then testing could be considered in the low-risk population. This review will demonstrate the ability to risk stratify more than 90% of all patients with clinically localized prostate cancer into low- or high-risk groups for biochemical progression following local therapy using four readily available pretreatment clinical parameters.