Fashion is a non-sustainable industry. One of the largest industries globally, fashion is considered one of the greatest polluters in the world – it contributes 10% of global greenhouse gas emissions, it generates nearly 20% of global water waste, and it produces yearly massive quantities of textile waste. Despite the efforts of researchers or pioneers at various levels of the industry, changes seem to take place slowly and isolated. Assuming that a real change in the industry must happen from the very initial stage of creation – the way we think and conceive fashion, this paper takes a closer look at the fashion design process. As studio-oriented research, the paper focuses on the designer’s work and highlights the designer’s responsibility during the multiple phases of creation. From concept development to materials sourcing, from recycling/re-using/repairing strategies to the new technologies of production, from slow fashion movement to multifunctional garments design – sustainable oriented actions must occur simultaneously at each stage of the design process. The conventional phases of fashion thinking are re-evaluated, embedding sustainable concerns into the studio standard processes. Relevant solutions and examples of best practices are further illustrated and analyzed. Emphasizing the importance of seeing sustainability as an integrated part of the design process, the paper aims to adjust the fashion designer’s mindset to function as a catalyst for the industry’s transformation.