As interest in sustainable fashion and localism mounts, there is a compelling need to foster purchasers’ trust in claims made by fashion businesses. Geographical indications (GIs) have proven successful not only in reducing consumers’ search costs through reliable labels but also in safeguarding identity and heritage and delivering added value for agricultural products. Building on the EU Commission proposed Regulation to protect craft and industrial products that rely on the originality and authenticity of traditional practices from their regions and drawing on the “fiber follows food” adage, this paper puts forward policy recommendations related to the proposed expansion of GIs to the fashion industry. Through cross-sector and transdisciplinary explorative research, this article provides evidence on how the origin link could be framed to accommodate apparel and footwear items within the scope of protection of the EU sui generis GIs system despite their “non-terroir” character. Key drivers and barriers to harnessing GIs’ potential and enhancing the sustainability of localized fashion production are further explored based on the theoretical insights and comparative practical experience extrapolated from qualitative interviews with GI-protected winemakers in Apulia. Ultimately, the paper increases the understanding of the economic, ecological, social, and governance implications, which need to be addressed to improve the sustainability impact of sui generis GI systems before expanding them to the apparel and footwear domain.