Central to understanding the chemistry of cells is elucidating the chemistry of important biomolecules and their interactions. A class of biomolecules of particular interest is enzymes; molecules that catalyse the broad range of reactions essential for life. In addition to the fundamental knowledge to be learned, this interest is due in part to the medical and industrial benefits to be obtained. For example, the aim of therapeutic drugs is often to enhance or inhibit the function of a specific enzyme. Computational chemistry uses computers to model the chemistry and reactions of chemical systems. Such approaches are used, for example, to study problems that may be too difficult to study experimentally or to provide insight into observed phenomena. Our research group uses the methods of computational and theoretical chemistry to investigate the chemistry and reactions of various biomolecules, in particular biochemical catalysts. Brief overviews of some various areas studied by our group are described below.