In addition to teaching architecture and urban design in the architecture program at the University of Maryland, Bell has been active throughout the Washington/Baltimore region with professional projects ranging in scale from waterfronts, new towns and neighborhoods to civic and mixed-use buildings and schools. He has served as president of the Neighborhood Design Center in Baltimore and Prince George's County, Maryland, assisting communities and community groups in matters of design and planning and from 1994 to 1999 Bell was the Director and conference chair of the Northeast Regional meeting of the Mayor's Institute for City Design, sponsored by the National Endowment for the Arts. His work has been exhibited at the Triennale di Milano and in 2006 he served as a juror for the Biennale of Venice (Italy).