Over the last decade design fiction, the speculative design method, has been cultivated within the design community. It has been increasingly adopted, or at least experimented with, in various areas of government, industry and academia, as new methods to engage with potential futures are sought out. Orienting design practice as an overtly fictive act, design fictions are a form of worldbuilding used variously in the service of rhetoric, innovation and research. The method has been the preserve of designers, researchers and artists working in industry and academia, with a particular nexus between design and HCI. The design fiction works that they create often focus on the normative. Though non-normative perspectives are generally elided in the development of the method, Participatory Design --an approach to design that involves stakeholders as co-creators in design processes-- has, until recently, demonstrated minimal interest in adopting speculative practices. Working from an egalitarian impulse, the thesis explores design fiction as a participatory practice.

Taking Research through Design as a methodology, the study offers reflections in, and on, the facilitation and prototyping processes undertaken by the author and others as part of two design projects which worked with older people on government policy in the UK; ProtoPolicy and What If?. Two methods bricolage and black an adapted annotated portfolio were used. The use of bricolage as a method allowed me to develop artefacts as part of an iterative conversation between practice and theory. This process explored and diagrammatically visualised the concept of heterotopia and other relevant theories as a potential theoretical framework supportive of a participatory approach to design fiction. The portfolio gathered together products of the external participatory design fiction projects in a thematic exploration of participation, design fiction and heterotopia.

The thesis offers two contributions to knowledge. The first is speculative heterotopia, a theoretical framework to underpin a participatory approach to the design fiction method. The second is a scaffold to guide design facilitators in supporting participants through the possibilities within a design fiction project. The thesis concludes by highlighting issues for facilitators and participant groups created by adopting a participatory approach to design fiction making use of speculative heterotopia.