It was over five years ago that the Centre for Medicines Research organized a workshop entitled "Quality of Life: Assessment and Application". This workshop brought together a unique group of participants, some of whom had been involved in studies on quality of life for well over a decade, whilst others were meeting the subject for the first time. This blend of experienced researchers and enthusiastic newcomers was a great stimulus to the discus- sions which followed individual presentations as well as that resulting from the study groups. In the ensuing publication, a balance was sought between a consideration of the complex principles underlying the assessment of quality of life and the application of such assessments to specific clinical conditions which necessitated this approach. The organization in 1991 of a second workshop entitled "Quality of Life Assessment: Key Issues in the 1990s" resulted in a further consideration of the quality of life philosophy, concepts and key instruments together with an update on assessing quality of life in a number of major disease areas. Of particular importance was an examination of various viewpoints concerned with ethical questions and their implications, and quality oflife from industry, regulatory and health care purchasers' perspectives. As a result of this second workshop, the editors of the original book referred to above decided to produce a second edition with a number of updates and additional chapters.