 The case study approach is a valuable methodology in exploring complex issues in real-life settings, recognised in fields such as business, law, and policy, but less so in health services research. This paper reflects on different types of case study design, research questions it can answer, data sources used, advantages and disadvantages, and provides key pointers for designing and appraising proposals and a checklist to assess the quality of case study reports. This article was authored by hubby guru, Robertson Ann, Cresswell Catherine, and others.