The invention provides dual specific antibodies and methods of making and using such antibodies. In general, the dual specific antibodies are generated by identification of a monospecific antibody having light chain variable region VL residues that are electrostatic or hydrophobic and altering the nucleic acid sequence encoding one or more solvent accessible residues in the VH of the antibody either alone or in combination with alteration of the nucleic acid sequence encoding the VL of the antibody. The altered VH and the VL are expressed and dual specific antibodies, or antigen-binding fragments thereof, are selected. Exemplary dual specific antibodies are also provided as well as methods of using the antibodies.
