The pathogenesis of prostate cancer reflects complex interactions among environmental and genetic factors. Recent advances suggest molecular mechanisms that may explain geographic and ethnic variations in prostate cancer incidence, and understanding of molecular disease progression is advancing rapidly. Clinically, the case for screening has become stronger, and declining prostate cancer mortality rates may be due in part to early detection and treatment. Improved risk assessment for patients with localized disease is now available, although further refinement in predictive algorithms will need to incorporate validated molecular prognostic markers. Treatment options for patients with localized prostate cancer have expanded and the role of androgen deprivation further delineated. Finally, treatment strategies for patients with androgen-independent disease have also expanded, although novel therapies are required to improve survival in this group of patients.