We can trace cell-cell recognition to protein-protein interactions of cell surface adhesion and receptor proteins. These proteins are vital to multi-cellular processes as they recognize and integrate signals arising from the extracellular environment. In my lab, we study the interactions between cell surface proteins that underlie important biological phenomena in the nervous and immune systems. In addition to developing our own bioinformatic methods, we combine biochemical and biophysical approaches that include x-ray crystallography.