The importance of supporting carers in their roles is now recognised in government policy at all levels and there is ample scope for improving the service system as well as the evidence base for promoting effective interventions. This paper summarises the findings of a project to review the literature on effective caring that was carried out as part of a larger body of work by one research centre working in the area of carer needs assessment. The aim of the project was to identify best practice models, as well as particular types of services that may benefit specific sub-groups of carers, identify priorities for improving routine practice in carer support, and to outline an agenda for research and development. The type and strength of the evidence was summarised through the use of a classification system related to the strength of the evidence on interventions. The aim of a research and development strategy for the carer support sector would be to strengthen a "virtuous circle" where effective services, based on better use of evidence, and communication of the findings, leads to better policy to support even more effective services.