Mead was commissioned a midshipman and entered the Royal Australian Naval College at HMAS Creswell for junior officer training on 16 January 1984. He graduated from the college as a sub-lieutenant and with a Diploma of Applied Science in 1986 and undertook further training in bridge watchkeeping and clearance diving, specialising in Mine Warfare and Explosive Ordnance Disposal. Mead later described his service with the Clearance Diving Branch, culminating with his appointment as executive officer of Clearance Diving Team One, as "some of the happiest days of my career." Seeking to enhance his future career prospects, Mead trained as a Principal Warfare Officer specialising in Anti-Submarine Warfare. He also read for a Master of Arts in International Relations at Deakin University and, later, a Master of Management at the University of Canberra. A series of seagoing appointments followed, including as Anti-Submarine Warfare Officer aboard and in, and as Fleet Anti-Submarine Warfare Officer. Mead next returned to HMAS Arunta as executive officer. During his time in the ship, Arunta deployed as part of Operation Relex to turn back vessels suspected of unauthorised entry to northern Australian waters. Mead submitted the thesis for his Doctor of Philosophy, titled "The Australia–Indonesia Security Relationship", to the School of International and Political Studies at Deakin University in 2004. The following year, by now a commander, he was appointed commanding officer of the Anzac-class frigate. The frigate deployed to the Persian Gulf as part of Operation Catalyst, Australia's contribution to the Iraq War, in October 2005. During the six-month deployment, Parramattas crew carried out 186 vessel boardings and security patrols and were involved in training other coalition and Iraqi warships. Parramatta returned to Sydney in April 2006. Mead and his crew were subsequently recognised with a Meritorious Unit Citation for Parramattas "meritorious operational service" in the Persian Gulf, while Mead was additionally honoured with appointment as a Member of the Order of Australia in the 2007 Australia Day Honours for his "exceptional service in warlike operations". during exercise AUSINDEX-15 in September 2015. In 2007, Mead completed a course of study at India's National Defence College in New Delhi and, now a captain, was appointed Australia's Defence Advisor to India, Sri Lanka and South Africa. During this time Mead authored Indian National Security: Misguided Men and Guided Missiles, published with KW Publishers in 2010. Following promotion to commodore in July 2011, he deployed to the Middle East from October as commander Combined Task Force 150. Based in Bahrain, Mead's multinational naval task force was responsible for maritime counter-terrorism operations around the Arabian Peninsula and Horn of Africa. He returned to Australia in April 2012 as Commander Surface Force in Fleet Headquarters. For his "distinguished performance" as a "highly effective commander" in the Middle East, Mead was awarded a Commendation for Distinguished Service in the 2013 Queen's Birthday Honours. Promoted to rear admiral, Mead was appointed Head of Navy Capability in January 2015. In this role he was responsible for the development of present and future capability within the Royal Australian Navy, which included overseeing the lifecycle of projects and programs from initial concept through to disposal. After three years managing capability, Mead succeeded Rear Admiral Stuart Mayer as Commander Australian Fleet on 19 January 2018. In the 2020 Queen's Birthday Honours, Mead was advanced to Officer of the Order of Australia in recognition of his "distinguished service to the Royal Australian Navy in senior management and command roles."