This is a local, Japanese, prospective, longitudinal, observational, company-sponsored, multi-center, single arm study that will describe treatment satisfaction with Ra-223 in 150 bone metastatic CRPC patients on 1st to 3rd line CRPC therapy. All outcomes will be obtained using PRO questionnaires at 4 time points: before treatment, during treatment, and at 1-month after the last treatment cycle.