Gösta Gahrton, MD, Karolinska University Hospital, Stockholm, Sweden, discusses the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) as salvage therapy in multiple myeloma. Some studies have shown that relapsed patients who undergo a combination of allo-HSCT and autologous hematopoietic stem cell transplantation (auto-HSCT) have a longer long-term overall survival (OS) than patients who only receive auto-HSCT. Other studies have reported high short-term OS in relapsed patients treated with novel conditioning and consolidation approaches, including bortezomib after auto-HSCT. Dr Gahrton argues that allo-HSCT might be beneficial for high-risk patients and patients who have relapsed after auto-HSCT. In addition, Dr Gahrton describes how autologous chimeric antigen receptor T-cell therapy (CAR-T) could be consolidated with allo-HSCT, with early data on allogeneic chimeric antigen receptor T-cell (CAR-T) therapies showing efficacy in the relapsed setting. This interview took place at the 6th Congress on Controversies in Stem Cell Transplantation and Cellular Therapies (COSTEM), which took place virtually.