This literature review is concerned with the effectiveness and cost-effectiveness of support and services to informal carers of older people in England and Wales. It has been undertaken by the Personal Social Services Research Unit at the request of the Audit Commission (the Commission). The review is divided into three parts. It begins with an introduction summarising key issues that need to be considered when looking at the effectiveness and cost-effectiveness of services for informal carers. This is followed by an examination of the literature on the effectiveness and cost-effectiveness of the different services that may be used, directly or indirectly, to support informal carers. Finally, the third part provides a summary and some conclusions.