Computer-implemented methods of designing an antibody that will bind to a target epitope are disclosed. In one arrangement, the method comprises identifying one or more hotspot residues that will each bind to a corresponding one of one or more hotspot sites on the target epitope. Candidate antibody structures are selected from a database such that characteristic atoms within the antibody structure and hotspot characteristic atoms can be superimposed computationally with an averaged spatial deviation less than a predetermined threshold. A designed antibody is generated by replacing matching residues with different residues such that a predicted affinity is increased.