As an action-oriented and principle-driven field, health promotion is complex by its very nature. Thus, health promotion research requires approaches that take this complexity into account. The mixed methods approach is one promising possibility, which offers a framework to integrate different perspectives to the study of human phenomena. The core assumption underlying mixed methods is that the combination of qualitative and quantitative approaches provides a broader, more credible understanding of a research problem than the standalone use of either approach. This paper highlights the opportunities offered by mixed methods but also their limitations for health promotion research. It is built both on theoretical and on practical insights and focuses on three main challenges faced by health promotion researchers: linking research purposes and methodological choices; supporting participation, empowerment and emancipation; and providing knowledge in support of programme transferability. The chapter discusses the opportunities offered by mixed methods to develop supportive environments for both health promotion and research as well as to reflect on the researcher's position. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.