Background The continuous process of mental impairment in many nursing home patients leads to communication problems that make ethical decisions challenging. To ensure dignity, the communication process about end of life care should start while the patient is still capable of being actively participating.

Aim To examine the implementation of advance care planning in Norwegian nursing homes (NHs). Determine whether advance care planning is more effective in improving the quality of life and mental health than the usual care provided to people living in nursing homes.

Design This randomised controlled trial is being carried out in 60 Norwegian long-term-care units in the period of 2014–2016. Each unit will be treated as one cluster and will be randomised to either the intervention or the control group. The intervention group gets to follow an educational program, and they are systematically followed-up by phone to support the implementation. The control group receives care as usual. The study entails a 4-month intervention with a 9-month follow-up.

Discussion This study includes collaboration between physician, nurse, patient and next of kin. It will describe the effect of focusing on advance care planning by following an educational program based on international research. It is of high priority to provide more comprehensive training for staff working in nursing homes. Intervention with advance care planning will be a part of a larger study named COSMOS, and the educational program combines the most effective research within advance care planning, pain assessment and treatment, medication review, and occupational therapy.