Decolonizing science is essential for achieving a sustainable ocean and fostering a holistic approach to marine stewardship. Historically, ocean science has been dominated by Western methodologies, often side-lining Indigenous and local knowledge systems. This exclusion has not only limited the scope of scientific understanding but has also marginalized communities with profound, place-based insights into marine ecosystems. Indigenous people and local communities (IPLCs) have stewarded coastal and ocean spaces for millennia, drawing on ecological knowledge and cultural practices deeply rooted in their interactions with these environments. Recognizing and integrating these knowledge systems into mainstream ocean science is thus critical for achieving sustainable, equitable, and culturally relevant decision pathways to support globally agreed targets such as SDG14. In many cases, Indigenous knowledge systems provide insights that Western science lacks, especially in understanding long-term environmental changes, species behaviour, and ecosystem dynamics. By embracing Indigenous knowledge, science can expand its toolkit, enhancing resilience and adaptability in the evidence base to guide decision making. A genuinely inclusive approach to ocean sustainability also calls for rethinking power dynamics in marine governance and research. New mechanisms are required to ensure that a level playing field is created so that pathways towards sustainability are shaped by the needs and values of those directly impacted by ocean degradation. The emerging International Platform for Ocean Sustainability (IPOS) aims to contribute to this inclusive approach. A Handbook of Best Practices has been developed to guide the substantive design of the services to be provided, the composition and processes of selection for its institutional arrangements, as well as robust co-construction principles and equity guidelines. An IPOS shaped by these best practices will contribute to more adaptive and responsive ocean science, which in turn can provide a repository of evidence for informed decision making. This inclusive approach is indispensable for tackling the complex challenges of ocean degradation, as it bridges gaps between local insights and scientific innovation. Ultimately, by embracing all knowledge systems, ocean science can move toward a future that respects cultural diversity, fosters resilience, and sustains both human and ecological communities.