Cavendish boasted an active Literary Society, and Montgomery was a prominent member in the early 1900's while she was living there with her grandmother and assisting in the post office run out of the Macneill kitchen. Montgomery gave recitations and read papers. She also helped to edit the Cavendish Literary Magazine. Cavendish was a literate and articulate community, and Literary meetings were social events where people exchanged ideas about books, whether from the Cavendish Lending Library or elsewhere. Montgomery drew on her years at Prince of Wales College (1893-94) and Dalhousie University (1895-96) as well as on her stint on the newspaper, the Daily Echo in Halifax (1901-1902).

Montgomery's ten months on the Halifax newspaper stood her in good stead throughout her career. She became active in the Canadian Women's Press Club when she lived on PEI. In newspaper write-ups about Earl Grey's visit to the Island in September of 1910, Montgomery was described as the Maritime Provinces' Vice-President of the Canadian Women's Press Club. Marjory MacMurchy of Toronto was serving then as President of the Canadian Women's Press Club. When Montgomery later lived in Leaskdale, Norval, and then Toronto, she was involved in the Toronto Women's Press Club and Canadian Women's Press Club activities, frequently the guest of Marjory MacMurchy (later Lady Willison).

When Montgomery visited Boston in 1910, she attended the 25th anniversary of the New England Women's Press Club. She pasted into her scrapbook a lengthy write-up about the event and a photograph of Lilian Whiting, long-time American journalist and best-selling author who had written on the "unseen" and her psychic connections with Kate Field and Elizabeth Barrett Browning. In Boston, too, Montgomery visited the Authors' Club.

For years at Leaskdale she served as honorary president of the Hypatia Club (a reading and discussion club for women university graduates) that met in Uxbridge. She belonged to the Canadian Authors' Association in addition to the Toronto Women's Press Club and the Canadian Women's Press Club. The scrapbooks have pages of clippings about meetings she attended or where she was honored. (see Public Readings)

In 1916, when she was breaking away from L.C. Page in Boston, and turning to John McClelland in Toronto as her agent, McClelland advised her to join the American Authors League. She did so, and when her lawsuits with Page began, she was able to request a lawyer from the League.

While in Ontario, Montgomery became friendly with authors Marshall Saunders, Nellie McClung, and Marian Keith (Mrs. Duncan MacGregor). She became an increasingly powerful advocate for Canadian writing (see Public Readings and Changing Perception of Montgomery's Writing).