Objective: This study explores how companies across various industries are implementing circular economy strategies in practice, focusing on the drivers, practices, challenges, enablers, and outcomes of their efforts. Theoretical Framework: The study draws upon multiple theoretical perspectives, including the multi-level perspective on sustainability transitions, the resource-based view of the firm, and institutional theory, to understand the complex factors influencing the adoption and implementation of circular economy strategies. Method: A qualitative, multiple-case study design was employed, involving semi-structured interviews with key informants from 20-30 companies actively engaged in circular economy initiatives. Data were analyzed using a combination of deductive and inductive coding approaches, with member checking and peer debriefing used to enhance trustworthiness. Results and Discussion: The findings reveal that environmental sustainability concerns are the primary driver for companies adopting circular economy strategies, with regulatory pressures, competitive advantage, customer demands, and resource scarcity also playing significant roles. Companies are implementing a wide range of circular economy practices, including eco-design, circular business models, reverse logistics, and industrial symbiosis. Key challenges identified include lack of technical knowledge and skills, inadequate infrastructure and technology, and regulatory barriers, while enablers such as leadership commitment, collaboration and partnerships, and employee engagement are crucial for successful implementation. The study also highlights the positive outcomes of circular economy adoption, including environmental benefits, economic gains, innovation and competitive advantage, customer satisfaction, and employee engagement. Research Implications: This study contributes to the theoretical development of the circular economy field and offers practical implications for managers and policymakers. Originality/Value: This study addresses the lack of comprehensive, cross-sectoral research on circular economy implementation in practice, providing valuable insights into the experiences of companies across different industries.