Multidisciplinary collaboration is considered to be very important for the education of pupils with special educational needs and particularly those pupils with the most severe disabilities. This research adopts a multiple case-study design in order to understand collaboration and the integration of services and the effectiveness of these among pupils with profound and multiple learning difficulties (PMLD) in Greece. The teams, choosing case studies in five special schools, considered 10 pupils and their parents. Reviews and analyses of the legislation; the use of diaries; participant observations and semi-structured interviews were used for the collection of data. Two different models of service integration which provide different opportunities to the inclusion of pupils with PMLD were revealed since schools have different methods of integrating health and social professionals. In the first model, the school works with outside services, whereas in the second, services are within the school. In addition, roles and responsibilities differ within the different models. Service integration and collaboration were found to be more effective in schools where teachers and health and social professionals work under the same management. The study suggests the expansion of the second model of multidisciplinary collaboration with the integration in schools of health therapists, educational psychologists and social workers. (Contains 1 note, 2 tables, and 2 figures.)