Most men diagnosed with prostate cancer are more than 65 years of age. Therefore, a discussion of the issues surrounding the diagnosis, prevention, and treatment of prostate cancer in older men is, in many ways, a review of prostate cancer in general. Nonetheless, older patients with prostate cancer are often faced with a different set of problems than younger patients. For instance, if preventive strategies prove useful, they will have important implications for older men. Even a significant delay in diagnosis could greatly benefit the elderly population. Prostate-specific antigen (PSA) screening is controversial for men of any age but, for older men, screening may impart a risk to quality of life that may outweigh the potential advantages of diagnosis and treatment. Results of a large follow-up study of patients treated with radical prostatectomy suggest that even men with rising PSA values after surgery can have a relatively benign and protracted course. The survival rates noted in this study, however, were only for a select population of surgical patients, and, in fact, higher prostate cancer death rates have been observed for patients adopting the watchful waiting approach. Older men who request some form of primary therapy are increasingly being treated with brachytherapy, despite the lack of randomized trials demonstrating efficacy compared to external-beam radiation therapy, surgery, or watchful waiting. Contrary to an often-held view, older prostate cancer patients may have more morbidity from long-term testosterone suppression than younger patients. On the other hand, chemotherapy seems to be as well tolerated overall in older patients as in younger patients.