Irene Ghobrial of Dana-Farber Cancer Institute, Boston, MA discusses the importance of understanding the biology of multiple myeloma (MM) to refine treatment options at the 2017 annual meeting of the European Society for Blood and Marrow Transplantation. It is crucial to gain a better understanding of the biology of MM, because the disease can manifest itself in different patients as a result of different causes, including cytogenetic abnormalities and mutations. This means that it is becoming increasingly important that therapies are tailored to each patient and addresses their specific etiology, also known as precision medicine. Precision medicine is currently a real possibility but to advance further it is important to understand why some tumor cells have a faster growth rate than others. Moreover, it is also crucial to be able to accurately predict how different etiologies will respond to the various types of therapies and drugs that are available presently. It seems that this is only the beginning of precision medicine, and there is great scope for it in the future.