This study is a realistic evaluation of Inquiry Groups, an initiative introduced in an educational psychology service in response to the drive towards providing a high quality service, that is based upon psychological theory and research, contributes to positive outcomes for young people, and is responsive to current changes and development. Despite a growing interest in organisational learning, there is very little existing research into organisational learning and improvement in Educational Psychology Services. Research and Development in Organisations (RADIO) is used to structure the study, and realistic evaluation is used to explore the links between learning (outcomes) and the factors supporting/ inhibiting learning for individuals, groups and organisations. Commitment to the initiative, opportunities for reflection, and relationships within the Service, are highlighted as three of the key supporting factors. The study proposes that EPSs can change in response to new knowledge and self-review, providing sufficient time is allocated, and the initiatives are carefully planned to consider organisational and group processes, and the individuals at the heart of the organisation.