The fashion industry needs to source new, sustainable materials in order to reduce its significant social and environmental impact. The challenge lies in finding a material that can be rapidly adopted and scaled to meet consumer demand—without compromising on performance or driving up costs. Sci-Lume Labs’ solution to this problem is Bylon: the truly circular apparel fiber that can deliver circularity without compromising on performance, scalability, or cost. Bylon drops into the same manufacturing equipment used to make nylon and polyester, meaning it can scale quickly and compete at low price points. Bylon offers familiar performance versatility, combining the capability and tunability of synthetic fibers with the moisture properties and circularity of natural fibers. Bylon can be made from biobased feedstocks like agricultural waste, not nonrenewable petrochemicals, enabling industrial scale production without requiring land that would better be used to grow food. Finally, Bylon is 100% recyclable—by both chemical and mechanical recycling technologies—and biodegrades in the natural environment, resulting in fewer persistent plastics in our ecosystems and food chains. In this talk, we will share Sci-Lume Labs’ latest progress in manufacturing and scaling Bylon for apparel, and discuss the triumphs and challenges of developing a new fiber in the midst of a rapidly transforming industry and planet. We will conclude with Bylon’s unique potential to transform the fashion industry by delivering circularity that scales, without compromise.