 He is a Fellow of The Institution of Engineers Australia and a Fellow of the Australian Institute of Company Directors.Gumley was previously CEO of the Australian Submarine Corporation (2002–2004), Vice President at Boeing in Seattle (1999–2001), CEO of aviation software supplier The Preston Group (1998–1999) and CEO of the entrepreneurial Global Lightning Technologies Group (1993–1997).In February 2004, Gumley was appointed the inaugural CEO of the Defence Materiel Organisation (DMO).