Nikhil Munshi, MD, from the Dana-Farber Cancer Institute, Boston, MA, discusses the biology of multiple myeloma (MM) at the 2017 annual meeting of the European Society for Blood and Marrow Transplantation (EBMT) in Marseille, France. He explains the steps in myeloma development, and highlights the importance of treatments targeting clones at the different stages of clonal evolution, not just the terminal clone. Dr. Munshi also points out the importance of understanding the different signaling pathways involved in clonal evolution and the interaction of the myeloma cell with the bone marrow microenvironment. He discusses how proteasome inhibitors can be used in multiple myeloma treatment by targeting several steps of the disease development.