Generation Z is frequently described as a generation that deeply cares about the environment. Yet in practice, this concern often fails to translate into actual willingness to spend extra on sustainable clothing. In India, fast fashion continues to thrive because of its low prices and rapidly changing trends, even as the apparel sector causes significant ecological damage through heavy water use, chemical pollution, and enormous textile waste. This highlights a clear disconnect between young people’s stated values and their real purchasing decisions. This thematic literature review brings together findings from 33 empirical studies published between 2017 and 2025. It examines Generation Z’s attitudes, purchase intentions, and actual buying behaviour towards sustainable apparel, with special emphasis on the Indian context. The studies consistently reveal that while young consumers show strong environmental awareness and favourable attitudes toward green clothing, most still choose cheaper fast-fashion items when it comes to spending their own money. Price emerges as the biggest obstacle by far. Although a growing body of research exists from countries such as China and Vietnam, very few studies focus specifically on India — despite its huge Gen Z population and important position in the global apparel industry. The review identifies recurring patterns around the Theory of Planned Behaviour and its extensions, economic barriers, the mixed role of social media, greenwashing, and interest in circular options like second-hand clothing and rentals. It underlines the pressing need for more India-centred research to better understand and address this intention-behaviour gap.