Karin Reinisch was educated at Harvard, studying chemistry as an undergraduate and subsequently training as a structural biologist during graduate work with William N. Lipscomb and postdoctoral work with Stephen Harrison. Since establishing her own laboratory in Yale’s cell biology department, she has been working to understand the molecular mechanisms underlying membrane biology. Since 2013, her group has been studying protein-mediated lipid transfer at contact sites where membrane-enclosed cell structures called organelles are in close proximity. She and her collaborators were central in the discovery of a family of proteins that function as bridges between organelles for the transfer of bulk lipids. The discovery was paradigm shifting as new organelles are now thought to arise largely through such protein-mediated bulk lipid transfer, rather than solely via vesicle fusion as previously believed. She was elected to the American Academy of Arts and Sciences in 2024.