The number of older adults will increase considerably in the next decades. Since age is the main risk factor for dementia and pain, the number of patients with both dementia and pain will also grow. When dementia and pain concur, their impact on the European society multiplies and asks for transnational solutions. It seems already now evident that pain is grossly undertreated in dementia. Other unanswered questions regard the underlying brain pathology, optimal pain treatment and care, etc. The lack of validated pain assessment tools has yet prevented major progress. A few centres in Europe have started relevant research but these are not yet linked in a systematic fashion. This Action will bring together leading researchers from a wide range of scientific disciplines. The major aim is the development of a comprehensive and internationally agreed-on assessment toolkit for older adults targeting the various subtypes of dementia and various aspects of pain, including pain diagnostics, cognitive examination and guidelines for proper assessment. Validation of this toolkit requires joint action of both basic and clinical sciences. Only hereby, the urgently needed improvement of pain management in dementia can start.