She returned to England to teach cartography at the University of Sheffield, and worked as urban planner at the Ministry of Housing and London County Council.
[1] Marcus worked for several years as a research associate in the Institute of Urban and Regional Development at the University of California at Berkeley and began teaching in the Department of Landscape Architecture in 1969.
She held a joint appointment in the Department of Architecture where she taught seminars on social aspects of housing design, environments for the life cycle, and sense of place.
[2] In her studies of Easter Hill Village in Richmond,[3] California and St. Francis Square in San Francisco,[4] she saw that semi-public open spaces in cluster housing foster a sense of community.
Marcus' own environmental autobiography and analysis of her self and growth are contained in Iona Dreaming: The Healing Power of Place, A Memoir published by Nicholas-Hays, Inc. in 2010.
In this book written after a double bout with cancer, she reveals the remarkable power of place to heal psychological wounds and restore the spirit.