The chapters in this volume describe a powerful emerging approach for the therapy of disease. Targeted drug delivery, that is control of the kinetic behavior, tissue distribution, and subcellular localization of pharmaco- logically active agents, offers an important means for improving the efficacy of a wide variety of drug therapies. This is particularly true for therapeutic approaches based on newer agents which are the products of recombinant DNA research. These agents, be they peptides, proteins, or oligonucleotides, tend to be larger, more complex, and less stable than traditional drugs....