 Imatinib has revolutionised the treatment of chronic myeloid leukaemia CML. The first clinical trials were conducted in 1998 in patients with advanced disease, and by 2002 imatinib was established as the standard therapy for all patients including those recently diagnosed. In spite of overwhelming evidence about its efficacy we still need to gain more knowledge about issues related to long term treatment with imatinib such as why some patients respond better than others, the development of side effects and the quality of life. 