Lavington Bonython became directly involved with the Adelaide City Council when he was elected as a councillor in 1901. He became an alderman in 1907, served as Mayor (1912-1913), and as Lord Mayor (1928-1930). His appointment in 1912 made Bonython the second youngest person to serve as Adelaide's Mayor, and during his time with the council he was noted for his focus on Adelaide's heritage. For much of his period as acting mayor and mayor he was a widower, and his sister, Mrs. H. A. Parsons, performed the role of Mayoress at official functions.