The underwater domain presents a uniquely complex and hostile operating environment, and it is emerging as an increasingly critical area for countries across the Indo-Pacific to fathom. Underwater Domain Awareness (UDA) is now a critical element of contemporary maritime security, extending beyond traditional Maritime Domain Awareness (MDA) to focus on the undersea domain, where strategic competition is rapidly intensifying. For maritime nations in the Indo-Pacific, information superiority beneath the surface has become crucial to safeguarding security, economic interests, and critical infrastructure.

Australia’s geographic position between the Indian and Pacific Oceans underscores the strategic relevance of the Indo-Pacific as a single, interconnected theatre. The shift from ‘Asia-Pacific’ to ‘Indo-Pacific’ reflects not only geographic realities but also India’s growing strategic centrality in the region. Within this context, the elevation of Australia-India relations to a Comprehensive Strategic Partnership (CSP) in 2020 has provided a strong foundation for deeper cooperation, driven by converging security concerns, particularly China’s expanding maritime assertiveness, and the shared imperative of maintaining freedom of navigation along the region’s vital Sea Lines of Communication.

As maritime democracies committed to international law and UNCLOS, Australia and India have expanded defence engagement through naval exercises such as AUSINDEX and MALABAR, with increased cooperation in complex submarine and anti-submarine warfare operations. UDA, while often treated as a subset of MDA, warrants distinct attention due to its technical complexity and growing strategic significance. Advances in acoustic sensing, data processing, and undersea technologies have elevated UDA’s role in both peacetime maritime industry and safety, as well as in modern conflict.

This scoping report is the first in a series of five and examines the evolving maritime risk environment in the Indo-Pacific, the strategic importance of UDA, and the technological developments shaping it. It highlights UDA as a promising avenue for Australia-India cooperation, building on complementary strengths such as India’s manufacturing scale and Australia’s niche intellectual property and research expertise. Recent defence dialogues and practical arrangements signal momentum toward deeper trust and capability-based collaboration. Ultimately, enhanced UDA cooperation offers both countries an opportunity to strengthen their strategic partnership while contributing to a free, open, stable, and prosperous Indo-Pacific.