Objective: To evaluate the efficacy of a practical, easily implemented, educational intervention in group format for informal carers of persons with dementia. Methods: Multi-centre, randomised, controlled, single-blind trial involving 292 family caregivers of patients with moderate dementia in Alzheimer's disease. Results: Participants valued program components which had a practical impact on their caring role. The intervention achieved minor effects on the participants' psychological quality of life and did not reduce carer depression. It was also not associated with a lower rate of patient nursing home admissions. A subgroup analysis suggested that the intervention actually promoted the decision for nursing home placement in caregivers who were over-burdened and not coping well when they entered the study. Conclusion: To improve dementia carer support, educational components might be intergrated into more comprehensive and individualised interventions which include problem solving and behavioural management strategies, ensure the transfer of newly acquired skills into the everyday context, and adequately deal with the emotional consequences of the caring role. Copyright © 2009 John Wiley & Sons, Ltd.