PURPOSE: To perform a national survey of radiation oncologists and urologists about the type of resources used and the level of evidence needed to change clinical practice in localized prostate cancer. METHODS AND MATERIALS: From a random sample, 1422 physicians were mailed a survey assessing the types of information used and what level of evidence could alter their clinical practice in prostate cancer. Multivariable logistic regression models were used to identify differences in physician characteristics for each outcome. RESULTS: Survey response rates were similar for radiation oncologists and urologists (44% vs 46%; P=.46). Specialty-specific journals represented the most commonly used resource for informing the clinical practice for radiation oncologists (65%) and urologists (70%). Relative to radiation oncologists, urologists were less likely to report utilizing top-tier medical journals (25% vs 39%; adjusted odds ratio [OR] 0.50; P=.01) or cancer journals (22% vs 51%; adjusted OR 0.50; P<.001) but more likely to rely on clinical guidelines (46% vs 38%; adjusted OR 1.6; P=.006). Both radiation oncologists and urologists most commonly reported large randomized, clinical trials as the level of evidence to change treatment recommendations for localized prostate cancer (85% vs 77%; P=.009). CONCLUSIONS: Both specialties rely on their own specialty-specific journals and view randomized, clinical trials as the level of evidence needed to change clinical practice. Our study provides a context on meaningful ways of disseminating evidence for localized prostate cancer.