John enjoyed a successful military career in service with Royal Signals, SAS and a number of higher command and staff appointments. As a Signals Officer, he gained experience in telecommunications, electronic warfare, security, and surveillance systems. He became a Chartered Engineer in 1981 and a Fellow of the IEE in 1985. He completed the Army Technical Staff Course and was selected to attend the Pakistan Army Command and Staff Course at Quetta, Baluchistan. With SAS he undertook operations in the Far East, Middle East and Europe. He pioneered several SAS techniques mainly in covert communications, counter terrorism and UK nuclear facility protection. He maintained close liaison with SAS as Honorary Colonel to one of their TA Units and as a board member of the SAS Association executive committee.

After leaving the Army and joined BT as their Director Security from which he retired in 2000 to start his own security consultancy. He was a Board Member of both NACOSS, and Inspectorate of the Security Industry (ISI), and a founder member of the National Security Inspectorate (NSI) and became a founding Fellow of the Security Institute in 1999. He remains an active emeritus member of the Risk and Security Management Forum (RSMF), a life member of the US led International Security Management Association (ISMA) but has now relinquished chairmanship of the Selwyn House Committee, comprising the corporate security directors of 20 FTSE companies. He has been a Non-Exec and Advisory Board member of several UK and international security companies.

He married his wife Marion in 1965 and they have two adult daughters, Jane and Claire, both now married, post professional careers, and bringing up the grandchildren.