Background: Individuals with intellectual disabilities often require various supports in their everyday lives. Many access both acute and intellectual disability services depending on their needs. Previous research has highlighted suboptimal experiences of care provided in acute services. Joint working between both services has been recognised as a measure of improving healthcare for this group. Although there is some evidence regarding this issue from the perspective of acute service providers, further research is required to understand the perspective of intellectual disability service providers. Methods: Ten nurses working in various roles in intellectual disability services across Ireland took part in semistructured interviews. The data were analysed using thematic analysis. Findings: Issues with inter-service communication and insufficient policies, protocols and pathways were found to negatively impact joint working. Acute services seemed to have a limited understanding of the role and capacity of intellectual disability services. Acute services do not always identify the individual needs of the people in their care. Despite this, there were examples of joint working taking place that benefited those with intellectual disabilities. Conclusions: Joint working needs to include improving communication between both services, co-developing policies, protocols and pathways and appointing acute care liaison nurses.