Ship biofouling is a major yet underregulated pathway for marine pest introduction. Australia is a globally recognised leader in marine biosecurity because its interconnected, multi-layered biosecurity system is built upon rigorous, multi-faceted scientific research. This framework operationalises scientific insights such as MIS risk analyses, studies on port residency times, and the temporal development of biofouling organisms through evidence-based tools like the mandatory Pre-Arrival Report and the ‘Vessel Check’ risk assessment tool. Despite this robust foundation, significant challenges remain in translating scientific monitoring into effective practice. This presentation is based on a mixed-methods approach of key stakeholders’ surveys, semi-structured interviews, and desktop analysis of relevant policy and regulatory documents. The findings show that, while Australia has integrated advanced strategies like eDNA surveillance, their implementation is constrained by financial, human and physical resources, gaps in organisational capability, work health and safety considerations, the absence of standardised mandatory measures, and increasing pressures from climate and environmental change. These challenges highlight the complexity of operationalising biosecurity across multiple system components. Addressing these barriers is critical not only for Australia but also for informing global efforts to manage ship biofouling. This paper reasons there is an urgent need to bridge the science-policy disconnect through strengthened collaboration and capacity-building partnerships, alongside regular review of international instruments to ensure responsiveness to evolving environmental conditions.