Aides-de-Camp attend the Lieutenant Governor at events and liaise with organizers on questions of protocol and ceremony. Each Lieutenant Governor appoints his or her own Aides-de-Camp, and some serve consecutive vice-regal representatives.

The Lieutenant Governor of Ontario is served by a corps of about 50 volunteer Aides-de-Camp, drawn from civilians and officers in the regular and reserve units of the Canadian Forces as well as the Ontario Provincial Police, Royal Canadian Mounted Police, St John Ambulance Brigade, Canadian Corps of Commissionaires, and other police, firefighter and EMS services.

Aides-de-Camp are entitled to the post-nominal "AdeC" after their names and to wear a badge of the Office they are serving. They may also wear the aiguillette, a braided cord worn on the right shoulder of those serving The Queen and her representatives.