Margaret M. Keith is an occupational and environmental health advocate and researcher, focussing particularly on women and work. She earned a PhD from the University of Stirling. Margaret served as Executive Director of the Windsor Occupational Health Information Service before joining the Occupational Health Clinics for Ontario Workers in Sarnia. She and her partner, Jim Brophy, assisted the First Nation’s community of Aamjiwnaang near Sarnia in exploring health problems related to environmental pollution from the adjacent petrochemical industry. Margaret was co-author of an internationally recognized research article documenting a skewed sex birth ratio uncovered after examining Aamjiwnaang birth records. She lives in Emeryville, Ontario.