Most of the information regarding the clinical characteristics of chronic myeloid leukemia (CML) patients are derived from clinical trial data, where any patients not fitting the strict inclusion criteria are excluded. Giuseppe Saglio, MD, of the University of Turin, Turin, Italy, highlights the importance of our knowledge of the characteristics of entire CML populations, before introducing the CML Italian Multicenter Observational Study (CML-IT-MOS), which aims to collect the clinical characteristics, hematologic traits and treatment response of non-selected Italian CML patients. This video was recorded at the American Society of Hematology (ASH) 2018 Annual Meeting and Exposition in San Diego, CA.