To meet the International Maritime Organisation’s (IMO) 2030 and 2050 decarbonisation targets, shipowners as well as cargo owners and charterers are exploring the purchase and use of green fuels. Biofuels can be a near-term measure to reduce GHG emissions as they are available today, and they can be deployed in the same way as marine fuels with minimal changes to the existing distribution infrastructure, shipboard technologies, and operational norms of ships. However, there is no industry-wide assurance framework that addresses concerns on the quantity, quality and GHG emissions abatement of biofuels, nor one that safeguards their premium and value. To address this gap, the GCMD-led pilot aims to establish an assurance framework that ensures supply chain transparency of drop-in biofuels, whose applicability can be extended to future drop-in fuels, such as bio-LNG, bio-methanol and green ammonia, when they become available in meaningful quantities.