School leaders hold key roles in the organisation of educational support. In several Swedish municipalities, municipality organisers and school leaders provide segregated special educational solutions (SSESs) for pupils diagnosed with neurodevelopmental disorders (NDs). This article aims to contribute with knowledge about the Swedish special education system, more specifically to illuminate school leaders' understanding of special educational provision designated for pupils diagnosed with NDs. Seven school leaders, with connections to SESSs in a Swedish educational jurisdiction, were interviewed. The article is influenced by the theory of critical pragmatism and the concept of systems thinking. The results indicate that, according to the school leaders, the regular school system is not adapted for pupils diagnosed with NDs, therefore SSESs are needed. However, the school leaders did not share a mutual understanding of SSESs. Equally, information flows and collaborations among the school leaders were limited. Several school leaders expressed scepticism about the municipality organiser's engagement and interest in the SESSs. Accordingly, SSESs appear as units that are de-coupled from the rest of the regular educational system. Various obstacles regarding prerequisites for systems thinking were identified, complicating school leaders' and the municipality organiser's mutual understanding and critical scrutinising of SESSs.