In 1954 she was appointed to the first Auxiliary Board along with eight others. Her area included western Canada, two-thirds of the United States from the Mississippi River to the Pacific Ocean, plus Alaska and Hawaii. Those appointed in North America were: Canada: Rowland Estall; United States and inter-America: William de Forge; Mrs. Margery McCormick; Mrs. Katherine McLaughlin; Mrs. Florence Mayberry; Dr. Sarah Pereira. While serving as an Auxiliary Board member, Florence was elected to the National Spiritual Assembly of the United States in 1959. [BW12p40]

Florence and her husband David pioneered to Mexico in 1961, where she was also elected to the National Spiritual Assembly of Mexico and she continued her service as an Auxiliary Board member. She was a delegate to the first International Convention to elect the first House of Justice.

In 1968 as part of a new development in the Faith to appoint Boards of Councillors in each continent, the House of Justice appointed Florence, along with Lloyd Gardner and Edna True as members of the North American Board of Counsellors. .

In 1973 she was appointed as one of three Counsellors of the newly established International Teaching Centre. For Florence and her husband David, this was the beginning of 10 years of service at the Bahá'í World Center. At the time of her appointment the International Teaching Centre consisted of the seventeen living Hands of the Cause and three Counsellor members, Hooper Dunbar, Florence Mayberry and 'Aziz Yardi. [Wikipedia; Find a grave]

See Wikipedia for her extensive bibliography as a mystery writer and her autobiography titled The Great Adventure published in 1994 bu Nine Pines Publishing.