In some circles, “fast” has become a proxy for a type of fashion that epitomizes ideas of unsustainability; yet high speed is not in itself a descriptor of unethical and/or environmentally damaging practices but a tool that is used to increase sales and deliver economic growth with attendant ecological and social effects. Questions about speed probe deeply into the economic systems, business models, and value sets that underpin the fashion sector today and which profoundly shape its sustainability potential. In this article, ideas and practices of the lexicographical opposite to “fast,” i.e. slow culture, are framed as an opportunity to begin to engage better with systems-level questions in the fashion sector in order to build deeper and longer-lasting change towards sustainability.