This paper provides an overview of the implementation and evaluation of the critical care assistant (CCA) role within a large teaching trust. Nine CCAs were employed as a pilot across six critical care units. A multi-stakeholder evaluation was performed to establish the impact of the new role on the critical care team and the contribution to patient care. The evaluation was undertaken over 6 months and used questionnaire format and focus group interviews. The results of the evaluation were overall mixed with some improvements noted especially within high-dependency care where the introduction of the role eased some of the workload pressures on qualified staff and allowed nurses to focus on the more dependent patients. A structured education and training programme supported by the National Vocational Qualification level 3 assessment strategy helped to prepare the CCAs theoretically for the extension in their role; however, difficulties were experienced with the appropriate allocation of tasks and general communication with nursing staff. The perceptions of both patients and relatives were sought and evaluated positively as they were satisfied with the standard of care received and were comfortable with a CCA providing their care, which supports the future development of the role.