This thesis explores how sustainability regulations influence organizational practices within Sweden’s women’s fashion industry. As the European Union introduces increasingly binding policies - such as the EU Strategy for Sustainable and Circular Textiles, the CSRD and the ESPR - fashion companies are facing new legal obligations that demand transparency, circularity and environmental accountability. Drawing on semi-structured interviews with managers, sustainability officers and employees from Swedish fashion companies, the study investigates how regulatory changes are interpreted, implemented and experienced internally. The findings reveal that while sustainability has become a strategic imperative, regulatory ambiguity and limited practical guidance present significant challenges. Managers often rely on personal interpretation, due to the lack of standardized processes, while employees experience increased administrative burden and limited engagement. The research highlights the importance of leadership communication, cross-level alignment and organizational learning in navigating this transition. By applying theoretical frameworks, including Kotter’s 8-Step Model, Lewin’s Change Model and the Sequential Sustainability Transformation Model (STM), the study offers a nuanced understanding of how regulatory change drives both disruption and transformation. Lastly, the thesis contributes to academic research on organizational adaptation and provides practical implications for fashion companies and policymakers who seek to enhance regulatory effectiveness and internal change capacity.