In forming its Quality of Life Group, the EORTC created one of the earliest and largest of such groups in Europe. The EORTC QLQ-C30 which this group developed has become the most widely used questionnaire in Europe for cancer patients, and is extensively used around the world. The Quality of Life Group continues to build upon this success, both by refining the QLQ-C30, whilst developing a range of additional modules, and by initiating research projects that explore aspects of quality of life assessment, evaluation and interpretation. We review the progress to date and indicate directions of further research and development.