Heymann is currently a professor in the Faculties of Medicine and Arts at McGill University, where she is also founding director of the Institute for Health and Social Policy. In addition, Heymann is an Adjunct Associate Professor at the Harvard School of Public Health and Harvard Medical School and founding chair of the Initiative on Work, Family, and Democracy.

For more than a decade, Heymann has been involved in research on working families and their children in North America and globally. With support from the Sloan Foundation, she is fielding a national survey on work, family, and community. With support from the Ford and Annie Casey Foundations, she is developing case studies on private companies who are economically succeeding while improving the lives of employees, their children and other family members who have lived in poverty. With support from the Ford Foundation, Heymann's team has developed a global index examining public policies that affect children and families. She has received FIRST and Shannon Awards from the National Institutes of Health to examine the relationships among community services, parents' work conditions and children's health. She was principal investigator on "The Behavioral and Cognitive Development of Children Living in Poverty," a research project funded by the William T. Grant Foundation. As a Picker Commonwealth Scholar, Heymann has been the principal investigator on a study which examines the health conditions faced by high need and resource poor families. Heymann served as chair of the Johnson Foundation program, supported by the Packard Foundation, on Work, Family, and Democracy.

Heymann received her Ph.D. in Public Policy from Harvard University, where she was selected in a university-wide competition as a merit scholar, and her M.D. with honors from Harvard Medical School. She trained in Pediatrics at the Children’s Hospital of Boston.

She has served in an advisory capacity to the United Nations Educational, Scientific and Cultural Organization (UNESCO), the U.S. Senate Committee on Labor and Human Resources, the U.S. Senate Committee on Health, Education, Labor, and Pensions, the World Health Organization, and the U.S. Centers for Disease Control and Prevention, among other organizations.

Heymann has more than a hundred publications, including, among others, Forgotten Families: Ending the Growing Crisis Confronting Children and Working Parents in the Global Economy (Oxford University Press, 2006), Healthier Societies: From Analysis to Action (Oxford University Press, 2006), Unfinished Work: Building Democracy and Equality in an Era of Working Families (New Press, 2005), The Widening Gap: Why America's Working Families Are in Jeopardy and What Can Be Done about It (Basic Books, 2001), and Equal Partners: A Physician's Call for a New Spirit of Medicine (University of Pennsylvania Press, 2000). Her articles have been published in leading academic journals in a wide range of fields including Science, the American Economic Review, the Journal of Policy Analysis and Management, the American Journal of Public Health, Pediatrics, the Journal of the American Medical Association, the American Educational Research Journal, and Community, Work, and Family among others.

Heymann's work has been featured on CNN Headline News, Good Morning America, National Public Radio's All Things Considered, Fresh Air and Marketplace, in the New York Times, Washington Post, LA Times, and USA Today among other nationally syndicated programs and press.