Background: Traditionally men with prostate cancer were treated in clinics created, managed and overseen by radiation oncologists. Urology-owned “integrated” practices emerged in the 2000s. Proponents of integrated (INT) practices argue they improve quality-of-care by fostering multidisciplinary care while detractors argue they decrease quality-of care because they employ only one or two radiation oncologists which limits quality-assurance peer review. We compared radiation techniques and treatment toxicity for men who received radiation therapy (RT) in INT and non-INT practices. Methods: Men 66 years and older diagnosed with prostate cancer from 2006 to 2009 were obtained from the Texas Cancer Registry. Cancer-directed therapy, comorbid medical conditions and late treatment toxicity (diagnosis or procedure codes for toxicity 12 or more months after diagnosis) were determined from linked Medicare claims. Practice type was classified based on practice location of the treating radiation oncologist. Chi-square statistics compared categorical variables. Cox proportional hazards models evaluated predictors of toxicity. Results: External beam RT (> 20 fractions) was administered to 781 men in INT and 3,257 men in non-INT practices. Median follow up was 44 months. Men treated in INT practices lived in counties with higher income (p<0.001). There was no difference in patient age (p=0.55) or comorbidity (p=0.88) between practice types. Men treated in INT practices were more likely to receive intensity-modulated RT (98% vs. 82%, p<0.001) and image-guided RT (73% vs. 23%, p<0.001). Androgen deprivation therapy use was similar between practice types (p=0.36). Adjusting for patient and tumor characteristics, there was no difference in risk of late gastrointestinal (p=0.52), urinary (incontinence, p=0.10; other p=0.28), or erectile (p=0.28) toxicity between practice types. Conclusions: Men treated in INT practices were more likely to receive intensity-modulated RT and image-guided RT for their prostate cancer. Risk of late gastrointestinal, urinary and sexual side effects for men who received radiotherapy in INT practices was similar to risk of late side effects for men who received radiotherapy in non-INT practices.