Operator. Overall command and control are maintained by a 'Bronze' officer. St John Ambulance Medical Response Teams remain unranked. Rank tables Rank review In December 2013 St John Ambulance officially announced its conclusion of the rank review that it had undertaken, subsequently issuing advisory documents to its members with detailed explanations. The review was developed to ensure that consistent and appropriate use of rank for positions, from the Unit up to the senior volunteers at National Headquarters. All existing ranks were removed and the new structure applied. Non-Commission Officer (NCO) ranks As a result of this rank review, it was decided to remove all NCO ranks for adult volunteers and staff across the organisation. Whilst these ranks have been removed for adult volunteers and staff, they still remain in place for Cadets. Assistants and deputies As a result of this review, Assistants and Deputies are no longer permitted through St John Ambulance, however additional team members may be added for geographical coverage. References See also Service Medal of the Order of St John Insignia of the Venerable Order of St John Non-military rank insignia Ranks and Insignia England-related lists