T he vision of personalized medicine is a compelling one for the future of medical care in general and cancer care in specific. It foresees the use of molecular data to better classify disease, facilitate the development and validation of new targeted therapies, treat patients with more specificity and efficacy but fewer adverse events, and more accurately determine disease predisposition. This vision drives most of the major strategic initiatives of the National Institutes of Health and the National Cancer Institute (NCI), and it is the principle behind recently drafted congressional bills such as the ''Genomics and Personalized Medicine Act of 2007.'' An issue that is intuitively obvious but rarely emphasized is that biospecimens of high quality are the sine qua non of personalized medicine. The molecular data that are the envisioned basis for personalized medicine must be derived from cells and tissues because, quite simply, that is where the molecules reside. Biospecimens such as cells, tissue, blood, and plasma are common requirements for patient management in current, standard-of-care medical practice. In cancer medicine they are the gold standard of diagnosis, staging, and prognostic/predictive factor analysis. In a world of personalized medicine, however, biospecimens will take center stage as the critical link between the clinic and the patient. To realize the vision of personalized medicine, patient-and disease-specific molecular data must be derived from biological specimens in an accurate and reproducible manner. This in turn requires that the biospecimens themselves be annotated, collected, processed, and, if necessary, stored and/or distributed according to standards that safeguard their quality. Otherwise, on either an individual patient or a medical enterprise level, the vision is reduced to the well-known aphorism of ''garbage in, garbage out.''
The reality of personalized medicine is on the horizon. The first steps have been taken in the evolution of tumor classification, disease prognosis, molecularly targeted treatment, and response to therapy based on molecular features. These represent some of the most important advances in cancer medicine over the past decade, but their development has been utterly dependent on the availabil-