Since the first edition of the Blended Finance Guidance in 2020, the blended finance industry has experienced significant growth and evolution. Blending is no longer an innovative approach; it is a well-known and widely used method for providers of development finance and the private sector to work together and leverage each other's resources and knowledge. Yet it still faces important challenges. Blended finance has not scaled as rapidly as hoped and has mobilised relatively limited private finance. It has remained a cottage industry with largely bespoke and fragmented interventions, as well as lack of standardisation and transparency. This updated edition of the OECD DAC Blended Finance Guidance reflects on these challenges and on how the field has changed. It offers strategic advice as well as practical insights for both policymakers and practitioners who want to use blended finance more effectively. The Guidance is based on lessons learned and feedback from many stakeholders. It highlights the importance of working together, building trust through transparency and improving the conditions for investment in developing countries. The Guidance is underpinned by case studies within a range of thematic areas that are critical for blended finance to work more effectively.