© 2019 John Wiley & Sons Ltd Aim and objectives: To explore multidisciplinary team members' perspectives of clinical nurse specialists in intellectual disability nursing contribution in Ireland. Background: While clinical nurse specialist roles have advanced over time, they are viewed as multifaceted and complex roles creating confusion. This confusion is reinforced by the absence of studies on multidisciplinary team members' perspectives on the activities of clinical nurse specialists. Design: A cross-sectional study of multidisciplinary team members (n = 262). The survey instrument was developed based on the literature and the result of a previous qualitative study and survey of intellectual disability clinical nurse specialists. Methods: SPSS was used for data analyses and descriptive and inferential statistics. The STROBE checklist for cross-sectional studies was used for reporting, and both a university and service providers granted ethical approval. Findings: This study highlights that multidisciplinary team members identify the contribution and support that intellectual disability clinical nurse specialists provide across a range of practice areas. Clinical nurse specialists support the care process through supporting clients, staffs, families, organisations, communities and other agencies. Conclusions: Overall, the study reports and acknowledges the significance and contribution of intellectual disability clinical nurse specialists, across a range of practice areas and the support they provide for all stakeholders within the care process. Relevance to clinical practice: Clinical nurse specialists are central to the nursing profession as a lead clinical role in practice and play a key role within the multidisciplinary team. Highlighting the work of the clinical nurse specialist creates greater clarity and less role ambiguity/confusion.