There is a growing imperative to address the negative environmental impact of fashion and an increased awareness of sustainability issues: the sustainable fashion concept (SFC). However, while consumers are becoming more aware and concerned about sustainability, this is not resulting in the purchase of sustainable fashion products in preference to “mainstream” goods. This so‐called attitude–behaviour gap is well documented in academic literature, and yet there is a lack of research into potential methods of disrupting this phenomenon. This study seeks to redress this by examining the potential influence of celebrity institutional entrepreneurs (CIEs) to raise awareness of the SFC and to therefore guide and change consumer behaviour towards more sustainable practice. CIEs are celebrities who use their social position to espouse their values with the intention of influencing institutional habits and behaviours. In this case, Emma Watson is identified as an appropriate and credible proponent, and her @the_press_tour Instagram account was used to examine her influence. A netnographic investigation of this account was conducted in combination with eight in‐depth interviews with account followers to examine attitudes and actions towards sustainable fashion. Findings showed that the account had partial impact on consumer engagement with the SFC in that it led to the participants being more likely to discuss and consider the issues around sustainable fashion; however, it had no significant impact on purchases of sustainable fashion. The study concludes that CIEs can impact the attitudes of mainstream consumers towards sustainable fashion; however, further research is required to determine any long‐term influence.

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