She is currently a Distinguished Professor of Molecular, Cellular, and Developmental Biology, and the Chief Scientific Officer of the BioFrontiers Institute at the University of Colorado Boulder.
After completing her postdoctoral training, Leinwand joined the faculty at the Albert Einstein College of Medicine in New York in 1981, where she eventually attained the rank of Full Professor and was Director of the Cardiovascular Research Center.
In 2003, she co-founded the Colorado Initiative for Molecular Biotechnology, which was formalized in 2009 as the BioFrontiers Institute, where she continues to serve as its Chief Scientific Officer.
She became a Howard Hughes Medical Institute Professor in 2006, and is an Ex-officio Board Member of the Global Down Syndrome Foundation.
Leinwand's excellence in teaching has been recognized by Howard Hughes Medical Institute's Professor Program.