She is Chair of the City Council Committee on Chicago Parks where she has worked to restructure the Chicago Park District and its management, improve programming, secure the parks and increase access to recreation for all Chicagoans with an emphasis on teenagers and youth. Mary Ann also is a member of the City Council Committees on Traffic Control and Safety, Buildings, Rules and Ethics, Budget, Finance, Historical Landmark Preservation, License and Consumer Protection and the Mayoral Task Forces on Lake Michigan and on Transportation. She serves on the city's Advisory Council on Chicago "Green" development and as a commissioner of both the Northeastern Illinois Plan Commission and the Chicago Plan Commission.

Mary Ann is proud of the diversity of the 48th Ward. She has worked to integrate immigrant groups into the mainstream business, financial and social structure of the neighborhood. An early supporter of the Human Rights Ordinance, she interacts closely with advocacy groups to protect the rights of all people. She formerly served as vice chair of the Illinois Citizens for Better Care, a group which advocates for nursing home residents' rights and was founder of the Committee Against Nursing Home Election Fraud.

Known for her concern for the environment, particularly Chicago's lakefront, Mary Ann represents the City of Chicago on the International Council on Local Environmental Initiatives. Formerly she served as vice-chair of the City Council Subcommittee on the Chicago Lakefront, as a vice-chair of the Lake Michigan Federation (now the Alliance for the Great Lakes), and a founding member of PCB's Gone. Her leadership on environmental issues earned a United Nations Environment Programme Award for Citizen Action to Protect the Global Environment and a fellowship to study urban planning in several European cities from the U.S./German Marshall.

Mary Ann and her husband Ronald, a professor at John Marshall Law School who recently served as chairman of the American Bar Association Criminal Justice Section, have lived in the Edgewater and Uptown communities for more than 30 years. They have two sons, Michael, a software engineer in Portland, Oregon, and Matthew, a clinical psychologist who also lives in the 48th Ward, three dogs and two cats.