In this article we examine how Pacific Island Countries (PICs) successfully championed a stand-alone Ocean Sustainable Development Goal (SDG) goal at the United Nations (UN). We analyse how the UN Post-2015 development process provided PICs with a unique opportunity to use their experience with collective diplomacy and regional oceans governance to propose this international goal. In this article we establish how PICs' national and regional quest to strengthen their sovereign rights over marine resources motivated their diplomatic efforts for an Ocean SDG. The campaign was a significant political achievement, positioning these Large Ocean Island States (LOIS) as global ocean guardians. We critically evaluate the effectiveness of the PICs' diplomatic campaign to secure an international commitment for an Ocean SDG. The PICs’ advocacy for Goal 14 under Agenda 2030 has enhanced their political effectiveness in the UN by improving their recognition by other States as leaders in oceans governance. We suggest their Ocean SDG campaign forms part of a distinct and continuing brand of oceans diplomacy from Oceania.