Coastal and marine ecosystems, such as mangroves, coral reefs and seagrasses, are critical to human well-being and global biodiversity. Infrastructure investments have a significant and increasing impact on these zones. This paper argues that a focus on Nature-based Solutions (NbS), as part of a blue infrastructure finance approach, can help to deliver measurably better outcomes. A key objective of this paper is to familiarise developers, policy makers and financiers with a robust approach to developing blue infrastructure in coastal areas: what is NbS, what are resilience planning approaches and what are means for blue infrastructure finance. The paper argues that standards and principles for developing and financing blue infrastructure and appropriate blended finance instruments can help to overcome remaining bottlenecks, scale up these approaches and attract more private financing into blue infrastructure. An important audience for the report are therefore private sector investors and multilateral financing institutions that are key to infrastructure finance. Convincing these critical stakeholders that blue infrastructure finance is not only possible and desirable but that it is both feasible and, ultimately, also financially more attractive is critical to achieve a just transition to sustainability. This report is the result of joint work by experts with a wide range of backgrounds, from finance, engineering and conservation, both in the public and private sector. Such a multi-stakeholder approach is most apt to address the blue infrastructure finance challenge ahead.