Multilateral consensus forged among heads of states must be value-additive and relevant at the national level to facilitate on-ground implementation. Yet, despite general optimism and advances in policy understanding, multi-scale diffusion remains a challenge with little certainty in outcomes. This study focuses on examining intermediary dynamics occurring within national policy apparatus that can influence domestic uptake of policy innovation. We analyse the anticipated spread of two supranational policies on coastal fisheries in the Pacific region – the ‘Small-Scale Fisheries Guidelines’ and ‘the New Song’ – in three countries: Kiribati, Solomon Islands and Vanuatu.