This chapter provides a conceptual and theoretical background for other parts of the book. It gives an introduction to key terms and ideas that recur throughout the volume. These include the understanding of fashion and sustainability in fashion design, production, and consumption the notion of the geography(ies) of fashion as a subfield of socio-economic geography, and evolving subjects of interest within it. Among these are issues such as factors influencing the location of fashion firms, independent fashion designers and brands; location of fashion retail; the notion of fashion quarters or districts; and the links between fashion, urban scenes, urban image, and branding. The potential contribution of fashion to the contemporary leisure economy and experience economy of cities; the links of this sector with the festivalisation of urban space and tourist attractiveness; and its scope for agency in the creation of spaces for social encounters are also considered. With reference to relevant publications, the text sets out to show how the geography of fashion intersects and dialogues with existing, more traditional subfields of human geography such as industrial geography (in particular research on global value chains, offshoring, and reshoring), geography of retail and consumption, geography of cultural and creative industries, or geography of events. It likewise shows how the geography of fashion fits into broader fashion studies as an area of interest in the humanities and social sciences. In this regard, reference is made to several spatial scales, as fashion production and consumption are complex geographic phenomena. On the one hand, they are heavily conditioned by globalisation processes. On the other, they are strongly influenced by local social, cultural, economic, and environmental contexts. The ecosystem approach is examined as a promising conceptual framework for the analysis of the fashion market referring to existing publications on entrepreneurial ecosystems and cultural and creative ecosystems. Its application includes the recognition of the diversity of stakeholders present in the fashion market and the myriad of potential links between them. The literature review points up interesting themes and research gaps such as over-representation of studies focused on major fashion centres, Anglo-Saxon and Western European or East Asian fashion markets, and the predominance of case studies rather than broader analyses at country level or a multidimensional, multiscalar perspective.