Nurture groups (NGs) are a form of provision for children with social, emotional, behavioural and learning difficulties. Although the first groups were established over 30 years ago, growth in the number of NGs in the UK has been exponential over the past ten years. This study attempts to assess the effectiveness of NGs in promoting positive social, emotional and educational development. The study set out to measure: (1) the effects of NGs in promoting pupil improvement in the NGs; (2) the extent to which these improvements generalised to mainstream settings; and (3) the impact of NGs on whole schools. Statistically significant improvements were found for NG pupils in terms of social, emotional and behavioural functioning. NGs which had been in place for more than two years were found to be significantly more effective than groups which had been in existence for less than two years. Pupils with SEBD in mainstream classrooms improved in behavioural terms significantly better than pupils with and without SEBD attending schools that did not have NG provision. The greatest social, emotional and behavioural improvements took place over the first two terms, whilst improvements in behaviours associated with cognitive engagement in learning tasks continued to improve into the third and fourth terms. This study suggests that NGs are a highly promising form of provision for young children with a wide range of SEBDs. There is also good evidence to suggest that successful NGs contribute to the development of the "nurturing school." (Contains 6 tables and 1 note.)