. It is proposed to achieve the selective delivery of cytotoxic agents through the use of bispecific antibodies. Taxol is a promising new anticancer agent isolated in low yield from the bark of the Pacific yew tree, Taxus brevifolia. The applicant will prepare a thioether-linked bispecific antibody with dual specificity for taxol and human cancer cells. It is asserted that this bispecific antibody will potentiate the action of taxol in target tissue, minimize side-effects, and reduce the total amount of taxol required for effective therapy.