After spending five years working in the architecture office of Richard Waite, Louise opened her own practice in October 1881, becoming the first professional woman architect in the United States. Robert Armour Bethune, a former colleague from the office of Richard Waite, soon joined her firm. Louise and Robert married in December 1881; a decade later, Bethune & Bethune Architects was one of Buffalo’s busiest and most prominent architectural firms.
Robert and Louise each assumed design responsibility, production of construction documents, and administration of their individual projects. Louise was responsible for all the “dwelling houses”, and she also enjoyed designing schools. She managed the office and was the primary financial stakeholder in the firm. Robert handled public relations and led most of the public projects.
Although there was little support at the time for women interested in pursuing a career in architecture, the natural connection between women and residential design was often described. Initially, Louise was enthusiastic about designing houses; however, by the 1890s she had cooled to residential work because of the low architect’s fees. Nonetheless, she continued to design houses; of Bethune & Bethune’s 180 known projects, 79 were single-family dwellings or mixed-use buildings with a residential component.