The Implementation Guidance reframes each Principle as a set of key considerations when developing a Nature-based Solution (NbS) in anOfficial Development Assistance (ODA) context. It highlights the importance of each key consideration to achieving the triple win for biodiversity, people and climate, as well as potential barriers and pathways to adoption. It also sign-posts a variety of resources that provide further guidance on how to incorporate the considerations into an NbS project. The Implementation Guidance is accompanied by a Checklist, which takes the key considerations and organises them under an operational or goals-based framework. The Checklist firstly considers project objectives and the local context, then economics and financing mechanisms, and finally institutions and governance. This approach makes the project objectives central tothe intervention, thus ensuring the triple win is effectively and efficiently addressed from the onset. The Checklist contains more considerationsthan the Implementation Guidance, either breaking considerations downinto more specific actions, or highlighting them under several stages ofproject implementation to emphasise their ongoing importance. The Implementation Guidance and Checklist may be used to provideguidance on best practices, as an evaluation framework to assessa project’s strengths and weaknesses, and as a framework to aidproject design and implementation. 21 Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist Nature-based Solutions Triple Win Toolkit: Implementation Guidance and Checklist