Thomas Cairns was inducted into Unami Lodge at Treasure Island Scout Reservation. Cairns served many years on camp staff at Treasure Island and on August 26, 1927 became the Order’s 63rd Third (Vigil Honor) Degree member. Cairns' Vigil Honor name was Achigiguwen “To Be Jocular”. In 1933 at the Chicago Grand Lodge Meeting Cairns was elected the Order’s ninth Grand Lodge Chieftain serving an extended three-year term to accommodate the scheduled 1935 National Jamboree. It was in this position that Cairns made his most significant contributions to the Order. As Grand Lodge Chieftain Cairns was charged with chairing and appointing Arrowmen to the Transition Committee responsible for all negotiations with the National BSA Council regarding integration of the programs. The Transition Committee became the National Executive Committee, the immediate predecessor of today’s National OA Committee. Cairns was responsible for setting up what would become the modern National Committee structure. In 1934 Cairns and his committee successfully completed the negotiation that allowed the OA to become an official BSA program. This also set-up the terms that the OA needed to meet to insure complete integration in 1948.
In 1936 and again in 1938 Cairns ran for and was re-elected to the National Executive Committee. Starting in 1938 Cairns as the first Vigil Secretary introduced the Vigil Certificate. Cairns also compiled the first comprehensive Vigil Honor list since the early years of the Grand Lodge when there were only 14 Third Degree members. Cairns continued to faithfully serve as Vigil Secretary until 1943 when his wartime responsibilities to the Red Cross necessitated his resigning from that position.
Thomas Cairns was one of the 11 inaugural OA Distinguished Service Award recipients at the 1940 National Meeting held at Camp Twin Echo. His DSA certificate read,
As national chief during the period of formal adoption of the Order by the National Council Boy Scouts of America, with complete revision of the entire organization and literature, his inspiring leadership and untiring efforts were exceptionally outstanding.