Research illustrates considerable academic work available for conceptualizing sustainability but relatively less in its application in the denim fashion business. Many scholars demonstrate that sustainability has various meanings and perspectives for humans, and its priorities alter decision-making for implementing fashion sustainability at the social, economic, political, and environmental levels. Due to the heterogeneous system of the fashion industry that involves complex consumption and production patterns among the diverse range of operations, fashion sustainability issues become wicked and systemic problems beyond the capacity of an organization, industry, or economy. Recent research conceptualizes a strategy that holistically evaluates the design of the fashion industry and identifies complex interrelationships with other sectors, communities, and global entities to tackle sustainability’s complexity and adopt sustainability concepts in the fashion business. This study explores how the denim industry can enhance sustainability performance and accelerate qualitative growth by implementing the Sustainable Development Goals centered on SDG 8, which acknowledges participation in fashion sustainability and profitable growth. The research led to semi-structured interviews of eight experts with comprehensive experience in the denim trade from different countries. The study used the constant comparative method to thematically analyze the professionals’ qualitative insights and intuitive perceptions of the fashion sustainability context under multiple business models across the fashion industrial system. The study conceives an idea of systemic change as a perceptual innovation generated from the Conscious Decision Mechanism (CDM), which includes systemic thinking and design enhancement of denim fabrication and trade for implementing enhanced sustainability concepts like circularity and regeneration in the fashion industry. The conscious decision mechanism fosters a trilogy of sustainability awareness, self-realization and an unconventional mindset that extends the role of a fashion professional to a systemic designer who re-thinks decision-making rules to influence a fashion company’s sustainability performance and systemic behavior. I perceive the conscious decision mechanism as a systemic phenomenon that determines the qualitative growth of the denim fashion business, transcending the conventional capacities of an organization, a country and even a generation to embed sustainability values in the fashion industrial system.