Effect measure long-term care? Main aim of interventions in medical care is to achieve health gains. Cost-utility analysis is an important instrument to assess relative efficiency of health care interventions. Main effect measure in a cost-utility analysis is ‘health-related quality of life’. Interventions in long-term care focus to a considerable degree on managing or reducing the effect of impairment on people’s daily lives and therefore on maintaining or improving well-being. Therefore health-related quality of life cannot be used to measure outcomes in long-term care aimed primarily at well-being. A first step in development of an outcome measure for long-term care is determining which domains of well-being this sector aims to improve. This article presents and discusses which aspects play an important role in the well-being of people with long-term physical, cognitive, psychological and/or sensory impairments. Keywords: long-term care; social care; outcome measures; instruments; economic evaluations