Peter Briggs retired from the RAN in 2001 after a 40-year career, specialising in submarines. This included two submarine commands, command of the RAN Submarine Squadron, director of Submarine Policy and Warfare and Head of Submarine Capability Team, established to rectify Collins introduction into service issues. He was the president of the Submarine Institute of Australia from 2006-09 and is a frequent contributor to public debate on Australian submarine matters.