Naval forces and defence contractors worldwide have been using applied acoustics' commercial off-the-shelf (COTS) acoustic tracking systems for many years. Working closely with military organisations, we have built an in-depth understanding of the operational and manufacturing standards required. Our systems are suitable for shallow water, short-range tracking for a team of military divers, as well as high-accuracy, long-range tracking to monitor and guide autonomous vehicles to their target. They are widely used for inspection purposes, intelligence gathering, and mine detection and disposal in MCM operations. Alongside our COTS solutions, these systems can also be supplied as OEM sub systems for simple integration into client systems.