Sage-Martinson holds a BA in political science and German from the University of Minnesota, and has a master's in public affairs in nonprofit management and community economic development from the Humphrey School of Public Affairs.

Saint Paul, Minnesota Mayor Chris Coleman announced July 3 the appointment of Jonathan Sage-Martinson as director of planning and economic development. He replaces Cecile Bedor, who is now the executive vice president for Greater MSP (Minneapolis Saint Paul Regional Economic Development Partnership).

Jonathan, a member of Minnesota Philanthropy Partners since 2008, has more than 15 years of community and economic development experience. He was the director of the Central Corridor Funders Collaborative, a 10-year initiative funded by 13 local and national foundations to promote the development of the Central Corridor light rail line to connect the downtowns of Minneapolis and Saint Paul. The new 11-mile line opened June 14, 2014.