The covalent linkage of enzymes that collaborate in a multistep reaction may have a beneficial effect on substrate conversion. Site-specific modification strategies ensure absolute control over the site of coupling. We show that well-defined enzyme architectures can be prepared via site-specific incorporation of novel functionalities into the model enzyme Candida Antarctica Lipase B (CalB). Different kinds of dimers were produced in which the covalent connection brought both active sites or both N-termini in proximity of each other. Dimers were as active as their respective monomers, both towards monofunctional substrates and molecules containing two substrate moieties.