Glycomics is an emerging field of research that examines the structure and function of glycans attached to biomolecules. Glycans are chains of sugars that often form complex branched structures on proteins or lipids. Study of glycans represents a previously “untapped” and overlooked field of inquiry in personalized medicine. In the past, technological approaches in personalized medicine heavily relied on high-throughput genotyping or gene expression analyses with relatively little exploration of the downstream biological processes such as glycans and associated variability among individuals and populations. Glycans are important modulators of numerous biological processes that determine person-to-person differences in susceptibility to common complex diseases and response to drug treatment. The heterogeneity and diversity of glycans in part reflect the genetic, population ancestry and age of each patient, as well as stages of disease and nutritional/environmental exposures. However, little effort has been made thus far to exploit the glycosylation state of a patient in relation to prevention of future disease risks or to determine the appropriate treatment for an individual patient. On the other hand, the vast heterogeneity and complexity of glycans limit their comprehensive study. Recent developments in glycan arrays now offer new possibilities in the horizon to achieve a high-throughput profiling of glycan diversity to discover novel molecular targets that are druggable, and better understand and predict variability in drug treatment outcomes. Glycan arrays present carbohydrate ligands in a manner that physiologically mimics interactions at cell-to-cell interfaces through multivalent binding. Glycomics can significantly complement the genomics and proteomics tools that are already being evaluated for developing personalized medicines. This paper aims to give an overview of the current status of glycan research and applications in diagnostic medicine. Moreover, we propose that glycomics and nanobiotechnology form a powerful and synergistic technological combination on the critical path to personalized medicine.