On March 30, 2022, the European Commission published the EU Strategy for Sustainable and Circular Textiles as part of the EU Green Deal, which aims to provide a coherent framework and a vision for the transition of the Textiles Clothing Leather Footwear (TCLF) sector. Following this scenario, the aim of the book is to explain circularity in fashion in simple terms. The author’s goal is to create a culture of circularity and to provide a practical read for both university students, entrepreneurs, managers and citizens alike. The book is enriched with some reflection questions and a circularity toolkit so that managers and professionals can test their circularity quotient and focus on the key aspects of circularity to accelerate the twin transition.