Current challenges in using immunotherapy for certain solid tumors include the immunosuppressive environment and the presence of cold tumors. Geertje Van Der Horst, PhD, Leiden University Medical Centre, Leiden, The Netherlands, comments on the therapeutic potential of pairing oncolytic viruses with immunotherapy. Oncolytic viruses can specifically target tumors and activate T cells prior to administering immunotherapies such as checkpoint inhibitors. Current oncolytic viruses undergoing clinical trials include talimogene laherparepvec, an engineered herpes virus for melanoma, and pelareorep, a reovirus for glioma and pancreatic cancer. This interview took place at the European Association of Urology (EAU) Meeting 2022.