The impact of localized prostate cancer in the elderly depends on disease aggressiveness and life expectancy. In men with localized prostate cancer, those with low-risk disease or a shorter life expectancy should be managed expectantly, whereas those with long life expectancy or more aggressive disease may benefit from curative treatment. Comorbidity and quality-of-life concerns are key considerations during the selection of therapeutic modalities in the elderly in localized and metastatic settings. A variety of new agents have changed the therapeutic landscape in castrate-resistant prostate cancer, but their benefits need to be considered alongside their side effects and cost.