The Social and Emotional Aspects of Learning programme (SEAL), designed to develop children's social, emotional and behavioural skills in the primary school, was part of the Primary Behaviour and Attendance Pilot funded by the then Department for Education and Skills (DfES) and piloted in 25 Local Authorities in the UK. The data collected in the evaluation of the pilot programme included pre- and post-intervention questionnaires for Key Stage (KS)1 and KS2 children in 172 schools, questionnaires for teachers, teaching assistants and head teachers in 29 schools and interviews with school staff and pupils in 13 schools. Of the school staff, 90% agreed that the programme had been at least relatively successful overall. All responding headteachers, 87% of teachers and 96% of non-teaching staff agreed that the programme promoted the emotional well-being of children, while 82% of teachers agreed that it increased pupils' ability to control emotions such as anger. Only 48% of teachers agreed that it reduced bullying, although this rose to 74% of non-teaching staff--suggesting that there was a greater impact on playground as opposed to classroom behaviour in this respect. The interview data indicated that the programme had increased staff understanding of the social and emotional aspects of learning and helped them to better understand their pupils, which changed their behaviour, enhanced their confidence in their interactions with pupils, and led them to approach behaviour incidents in a more thoughtful way. Analysis of the responses to the children's questionnaires revealed a range of complex relationships between age, gender, questionnaire responses made prior to the pilot, and school factors which made conclusive interpretation of the data problematic. (Contains 7 tables.)