The development of good-quality patient information is a major challenge to improve quality of cancer care. The SOR SAVOIR PATIENT program aims to improve patients' understanding of cancer treatment and to facilitate their participation in clinical decisions. This programme develops evidence-based information for cancer patients based on clinical practice guidelines in oncology, the "Standards, Options and Recommendations" (SOR) which are used as primary information sources. "Translation" of SOR guidelines to laymen uses a multidisciplinary approach involving specialists in cancer care, psychologists, linguists and anthropologists. The development actively involves cancer patients using focus group methods, individual interviews and postal surveys. The SOR SAVOIR PATIENT program is conducted by the FNCLCC and the 20 French regional cancer centres, with active participation of specialists (public and private), learned societies and institutions, collaborating in multidisciplinary working groups. The leaflets Understanding scanner and Understanding Magnetic Resonance Imaging available in this edition of Bulletin du Cancer have been developed by a multidisciplinary group (radiologist, oncologist, methodologist, health care practioners, psychologist, linguist) and 30 patients, experienced patients and caregivers. These leaflets stem from a collection of patients documents on radiological examinations (Understanding mammography, Ultrasound, etc.) which have been developed to help patients and caregivers to better understand these examinations.