<p>Aim To discuss and provide examples of how mixed-methods research was used to evaluate the integration of nurse practitioners (NPs) into a Canadian province.</p> <p>Background Legislation enabling NPs to practise in British Columbia (BC) was enacted in 2005. This research evaluated the integration of NPs and their effect on the BC healthcare system.</p> <p>Data sources Data were collected using surveys, focus groups, participant interviews and case studies over three years.</p> <p>Review methods Data sources and methods were triangulated to determine how the findings addressed the research questions.</p> <p>Discussion The challenges and benefits of using the multiphase design are highlighted in the paper.</p> <p>Conclusion The multiphase mixed-methods research design was selected because of its applicability to evaluation research. The design proved to be robust and flexible in answering research questions.</p> <p>Implications for practice/research As sub-studies within the multiphase design are often published separately, it can be difficult for researchers to find examples. This paper highlights ways that a multiphase mixed-methods design can be conducted for researchers unfamiliar with the process.</p>