Fast fashion is the business model of replicating recent catwalk trends and high-fashion designs, mass-producing them at a low cost, and bringing them to retail quickly while demand is at its highest. The term fast fashion is also used generically to describe the products of this business model, particularly clothing and footwear. Retailers who employ the fast fashion strategy include Primark, H&M, Shein, and Zara, all of which have become large multinationals by driving high turnover of inexpensive seasonal and trendy clothing that appeals to fashion-conscious consumers.

Mass production, also known as flow production, series production or continuous production, is the production of substantial amounts of standardized products in a constant flow, including and especially on assembly lines. Together with job production and batch production, it is one of the three main production methods.