Pharmacogenomics is likely to be among the first clinical applications of the Human Genome Project and is certain to have an enormous impact on the clinical practice of medicine. Herein, we discuss the potential implications of pharmacogenomics on the drug development process, including drug safety, productivity, market segmentation, market expansion, differentiation, and personalized health care. We also review 3 challenges facing the translation of pharmacogenomics into clinical practice: dependence on information technology, limited health care financing, and the scientific uncertainty surrounding validation of specific applications of the technology. To our knowledge, there is currently no formal agenda to promote and cultivate innovation, to develop progressive information technology, or to obtain the financing that would be required to advance the use of pharmacogenomic technologies in patient care. Although the potential of these technologies is driving change in the development of clinical sciences, it remains to be seen which health care systems level needs will be addressed.