Zimmerman was supervisor of occupational therapy and associate director at the Rusk Institute of Rehabilitation Medicine (IRM) in New York.[3] She taught occupational therapy courses at New York University from 1956 to 1974.[4] Her work as head of the institute's Self-Help Device Unit[5] focused on creating devices for rehabilitation, including the universal cuff, the Swedish Arm Support (deltoid aid), and finger splints, and on introducing assistive technology to disabled users.[6] She encouraged her clients to be resourceful in crafting their own tools and gadgets,[7] including everyday self-care items such as tableware and clothing.[8][9] She also established occupational therapy programs in other countries.[10]
Zimmerman was author of Self-Help Devices for Rehabilitation (1958), and co-author of Living with a Disability (1953, with Howard Rusk and Eugene J. Taylor), and Functional Fashions for the Physically Handicapped (1961, with Helen Cookman).[11] In 1960 she gave the Eleanor Clarke Slagle Lecture, titled "Devices: Development and Direction".[12]