Evidence is needed to validate rapid response teams (RRTs), including those led by nurse practitioners (NPs). A descriptive-comparative mixed-methods study was undertaken to evaluate a newly implemented NP-led RRT at 2 Canadian hospitals. On the basis of data gathered on 255 patients who received an RRT call compared with the patient data for the previous year, no significant differences in the number of cardiorespiratory arrests, unplanned intensive care unit admissions, and hospital mortality were found. In addition, no significant differences in patient outcomes were identified between the NP-led and intensivist physician-led RRT calls. A paper survey revealed that ward nurses had confidence in the knowledge and skills of the NP-led RRT and believed that patient outcomes were improved as a result of their RRT call. These findings indicate that NP-led RRTs are a safe and effective alternative to intensivist-led teams, but more research is needed to demonstrate that RRTs improve hospital care quality and patient outcomes.