The Spanish Group of Chronic Myeloid Leukemia, as a scientific association dedicated to the study of Chronic Myeloid Leukemia within the Spanish Society of Hematology and Hemotherapy (SEHH), has prepared the document presented here with the title "Manual for the control and treatment of patients with Chronic Myeloid Leukemia ”.In the last three decades there have been very important advances in the treatment of this pathology: universalization of allogeneic transplantation of hematopoietic progenitors, emergence of Imatinib, appearance of new generation inhibitors, generalized access to diagnostic and follow-up methodologies, discovery of mechanisms of therapeutic failure, possibility of a personalized choice of therapy, ...The development of the Manual tries to respond to the problems that arise from this dizzying progress. It contains all the information that the hematologist needs to take care of our patients. With more than 800 references, you can find everything you need to understand the genetic ins and outs of this leukemia, make the correct diagnosis, and prescribe the most appropriate treatment and monitor the response and safety. In addition, it manages to do so through the participation of the best experts in our country and with the collaboration of the representative group of LMC in Spain, alongside the SEHH.Excellent tables and figures are included that make the toughest explanations much more understandable and allow easy access to the diagnostic, response and follow-up criteria without making them as dry as they usually happen.