The standard treatment for advanced metastatic prostate cancer (PCa) is androgen deprivation therapy (ADT). And even if this is efficient in the short term, 1/3 of PCa will become resistant to ADT and develop castration-resistant prostate cancer. A new study, by Karolinska Institutet and others, shows that estrogen receptor β (ERβ) agonists together with ADT could be considered useful in the treatment.