The fashion industry is undergoing a significant transformation driven by sustainability demands and regulatory changes prompted by environmental concerns such as resource depletion, pollution, and unethical labor practices. Addressing these challenges requires the industry to adopt sustainable business models that integrate economic, social, and environmental considerations. This chapter investigates the development and implementation of Sustainable Business Models within the fashion industry, emphasizing their potential to align with the rising consumer demand for ethical practices and drive long-term success. The research proposes a comprehensive 3D SBM framework that examines value from creation, capture, and delivery perspectives. Drawing on data from various stakeholders in the fashion industry, focusing on Portugal, the study provides insights applicable across different contexts. It highlights a network perspective on value within the broader ecosystem in which businesses operate. The study underscores the critical role of SBMs in transforming the fashion industry by addressing sustainability challenges and meeting regulatory and societal demands. The proposed Ecosystemic Business Model emerges as a versatile framework adaptable to various industry contexts, promoting long-term success, resilience, and innovation. This approach ensures the sustainable growth of fashion companies and enhances their competitive edge in an increasingly conscious market landscape.