Within the software engineering community, deciding how to collect, store and use personal data has become about more than just understanding our users. This paper considers ethical data use which includes cultural considerations and data ownership rights. We discuss indigenous data sovereignty as a concept and how it potentially impacts technological solutions that gather personal data from users. We propose an extension to typical user-centred design processes which we call participatory data design. This incorporates the use of frameworks and tools that specifically focus on managing data within the cultural context it is gathered from. We also present a specific example of how we have used this approach in the context of a data collection project from M¯aori workers in New Zealand forestry. We conclude with a discussion of the wider implications of this approach.