Rosaline trained as an architect at the University of Waterloo from 1991-98 and worked as a junior architect in Toronto, Ottawa and London England. In 2001 she began working as an architect at Hobin Architecture in Ottawa, where she enjoyed an informal internship as a planning consultant. In 2011 she began her own architectural practice, continuing to provide planning consultancy; assisting infill housing developers in site assessments for highest and best use, and engaging in extensive community consultation. Since then, she has won multiple awards for infill housing projects, and 'Designer of the Year' in 2021. In 2019 she began research of infill housing patterns and neighbourhood change. In 2020 she initiated the ION Mapping Project, and developed ground breaking new approaches to plan the evolution of urban neighbourhoods. Her office has been hired by the City of Ottawa's Planning Department to assist in neighbourhood analyses, and has been instrumental in the City's shift toward form based zoning. In 2020 she founded Walkable Ottawa to collaboratively advance walkability in urban neighbourhoods. Rosaline became a certified professional planner in 2023.