Despite the significant survival benefit of taxane therapy in metastatic castration-resistant prostate cancer (mCRPC), all patients inevitably develop treatment resistance. An understanding of resistance mechanisms has led to new therapies for prostate cancer (cabazitaxel, abiraterone and enzalutamide), all of which have improved survival following first-line docetaxel. Another treatment, currently in development, targets the prosurvival molecule clusterin. Custirsen, an antisense molecule that inhibits clusterin production, has shown promise in combination with docetaxel in mCRPC patients at risk for poor outcomes. Although optimal sequence and combination of available therapies is unclear, the heterogeneity of mCRPC suggests a continuing need for personalized treatment regimens and improved abilities to predict which patients will respond to the available treatment options.