Androgen deprivation therapy is the cornerstone treatment for metastatic prostate cancer. It can be done either surgically or medically. Luteinizing hormone-releasing hormone agonists and antagonist are the most effective drugs, with different side effects and modes of action, but no clear efficacy differences. Adding a non-steroidal antiandrogen adds a marginal benefit but also significant side effects and costs. Non-steroidal antiandrogens should not be used as monotherapy. In most patients with metastases, immediate castration is the standard of care. The intermittent modality is apparently non-inferior to the continuous one, with some other benefits. Upfront chemotherapy added to castration should be considered as the new standard of care in many metastatic patients. Castration leads to many adverse effects, some potentially life-threatening such as cardiovascular side effects.