Several novel therapeutic agents have demonstrated ability to improve overall survival in metastatic castration-resistant prostate cancer (mCRPC) in recent years. With as many as 5 new agents approved within the last 5 years and an ongoing lack of comparative and prospective data, strategies for patient selection and sequencing of drug treatments are urgently needed. This review will summarize current clinical evidence and relevant molecular mechanisms in mCRPC. The understanding of these mechanisms may provide valuable assistance in making therapeutic decisions, especially while robust clinical data remain sparse.