Major General Jeffery John Sengelman, is a retired senior officer of the Australian Army. He joined the army via the Officer Cadet School, Portsea in 1980, was commissioned into the Royal Australian Infantry Corps and spent much of his military career in special forces. He commanded the 4th Battalion, Royal Australian Regiment (Commando) (2000–01) and the 6th Brigade (2010–11), deployed on operations to East Timor and Iraq, and served as Commander Forces Command in 2011, Deputy Chief of Army from 2011 to 2012, Head of Modernisation and Strategic Planning – Army from 2012 to 2014, and Special Operations Commander Australia from 2014 until his retirement in 2017.

The 2nd Commando Regiment is a special forces unit of the Australian Army and is part of Special Operations Command. The regiment was established on 19 June 2009 when the 4th Battalion RAR (Commando) was renamed. It is based at Holsworthy, New South Wales. The 2nd Commando Regiment trains and has served with coalition special forces units, and is highly regarded by these units. The regiment has been involved in operations in East Timor, Iraq and Afghanistan, where it was used in a direct action warfighting role. It has also been involved in domestic security operations including the 2006 Commonwealth Games and the 2014 G20 Leaders Summit. The regiment is the Command's capability lead for strike and recovery.