Sergeant Andrew Collier is a Royal Australian Armoured Corps soldier with over two decades of service across operational, instructional, and mentoring roles. He has served in cavalry, training establishments, recruiting, and capability development positions; with operational experience in border protection, Timor-Leste, Afghanistan and Cyber Security. His professional focus is on small-team leadership, influence, and the human dynamics that enable effective execution. He currently works with developing leaders across a range of training and operational environments.