Sustainable fashion is a term describing efforts within the fashion industry to reduce its environmental impacts, protect workers producing garments and uphold animal welfare. Sustainability in fashion encompasses a wide range of factors, including cutting CO₂ emissions, addressing overproduction, reducing pollution and waste, supporting biodiversity and ensuring that garment workers are paid a fair wage and have safe working conditions.

In 2020, it was found that voluntary, self-directed reform of textile manufacturing supply chains by large companies to reduce the environmental impacts was largely unsuccessful. Measures to reform fashion production beyond greenwashing require policies for the creation and enforcement of standardized certificates, along with related import controls, subsidies, and interventions such as eco-tariffs.

In the early 1990s, roughly coinciding with the 1992 United Nations Conference on Environment and Development, popularly known as the Rio Earth Summit, 'green issues' (as they were called at the time) made their way into fashion and textile publications. These publications featured companies such as Patagonia and ESPRIT. Doug Tompkins and Yvon Chouinard noted that exponential growth and consumption are not sustainable. In the late 1980s, they commissioned research into the impact of fibers used in their respective companies. Fiber and fabric processing are still the norm in sustainable fashion 30 years on.

In 1992, the ESPRIT e-collection was developed by head designer Lynda Grose and launched at retail. In parallel with industry, research around sustainable fashion has been in development since the early 1990s. The field includes technical projects that try to improve the efficiency of existing operations.

Northwestern University Library's Art Collection staff began developing a research collection of fashion materials around 2005, motivated by widespread student and faculty interest and by the increasingly scholarly nature of many fashion-related titles appearing in catalogs and approval plans.

In the European Union, the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulations required in 2007 that clothing manufacturers and importers identify and quantify the chemicals used in their products. In 2012, the world's largest summit on fashion sustainability was held in Copenhagen, gathering more than 1,000 key stakeholders in the industry. The Sustainable Apparel Coalition also launched the Higg Index, a self-assessment standard for the apparel and footwear industries.

In 2019, the UK Parliament's Environment Audit Committee published a report and recommendations on the future of fashion sustainability, suggesting wide-ranging systemic change, such as lowered value-added tax for repair services.

Fashion industry followers believe the business sector can act more sustainably by pursuing profit and growth. The movement believes that clothing companies should incorporate environmental, social and ethical improvements on management's agenda. This may include increasing the value of local production and products; prolonging the lifecycle of materials; and reducing waste. Another goal may be to educate people to practice environmentally friendly consumption by promoting the "green consumer".