The aims of the present work are to introduce to the field of communication between the cancer patient and the professionals, to remark the positive influence communication may have on the patient, and to present the EORTC communication questionnaire. Communication between patient and professional is a key element in the support that is offered to cancer patients. It is important to consider different professionals communicate with cancer patients. There is a need of research in communication between patients and professionals. Two main models of patient care are presented: Paternalistic and Patient-Centered Cancer Care. Patient-Centered Care includes Patient- Centered Communication - PCC. The relation between communication and other PROs - Quality of Life, Information and Satisfaction with Care - is presented. There are cross-cultural differences in communication that could be related to the model of patient care. The European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group is developing a questionnaire to assess communication between cancer patient and the professionals. This Communication questionnaire mainly assesses professionals’ behaviors. Cultural aspects have a key role in the development of the EORTC questionnaire. This instrument is based on the Patient- Centered Communication – PCC model. The EORTC QLQ-COMU26 is presented. It includes six scales and four individual items. The three phases of the questionnaire development process are described. At the present moment the EORTC QLQ-COMU26 is being field-tested in a larger international study (phase IV), to ensure it is an appropriate and psychometrically valid instrument.