There has been a significant growth in the infrastructure for archiving and sharing qualitative data, facilitating reuse and secondary analysis. The article explores some issues relating to ethics and epistemology in the conduct of qualitative secondary analysis. It also offers a critical discussion of the importance of engaging with the situatedness and contextually embedded nature of data, and ways in which contexts (including research designs and disciplinary and methodological assumptions) are themselves embedded in primary data. I illustrate some strategies for addressing these matters with reference to analyses of two different areas, drawing on research conducted as part of ESRC Timescapes, and highlight some issues for development research.