The intersection of the climate and biodiversity crisis with the COVID-19 pandemic is exacerbating the financial challenges faced by SIDS. Many now have debt-to-GDP ratios that exceed 100% and face liquidity and solvency issues. For Island Nations, ocean-based solutions including green shipping, offshore renewable energy, nature based solutions for adaptation, and sustainable seafood production are all areas of opportunity for the development of a pipeline of investable projects that can drive a transformational shift toward resilient, biodiversity positive, net-zero sustainable economies. To achieve this transformation requires unlocking capital at scale. Using philanthropic funding and blending concessional and non-concessional financing to catalyse private capital is the key to mobilise the investment needed to realise climate and biodiversity solutions. Focusing on ocean-based solutions, this roundtable discussion will invite participants to share experiences, ambitions and opportunities to scale up finance for SIDS. Organisers will present two vehicles for investing into ocean and climate solutions using philanthropic and private capital.