<p>The role of the clinical nurse specialist (CNS) remains an area of debate. To define this role, it is important to elicit the perspectives of stakeholders, such as the nurses working with the CNS and the patients. However, eliciting such views from those who are dependent on the CNS in some way – either for care or in terms of supervision – can be difficult. Therefore, this study applied a modified Delphi Technique to ascertain these views and define the role of the CNS in a haematology unit. The methodology can be applied to other specialist areas.</p>