Colman's research interests are in structural biology, especially of human B-cell lymphoma 2 (BCL-2). Colman determined the three-dimensional structure of the influenza virus neuraminidase and, in one of the earliest cases of structure-based drug design, discovered zanamivir, the first-in-class neuraminidase inhibitor for influenza. His subsequent structural studies on resistance to this drug class suggested how to design drugs against moving targets. His discoveries underpin drug stockpiling for pandemic preparedness. He has made seminal contributions to structural studies of antibodies and antibody-antigen complexes. Recent[when? work on apoptosis solves the long-standing problem of how pro-apoptotic Bax changes conformation to dimerise and then oligomerise and permeabilise the mitochondrial membrane, an essential step in the intrinsic cell-death pathway.