The Human Genome Project and other large scale sequencing consortia continue to generate huge amounts of DNA sequence data. Despite the identification of specific disease-related genes and genetic markers, we still appear to know little about how diverse gene products actually interact with each other or respond to other chemical or biological stimuli. Such information is of course fundamental to understanding complex disease pathways and biochemical processes and, as such, has spawned new fields of investigative genetics, that of functional genomics and proteomics. DNA array technology is emerging as a powerful, high-throughput and versatile tool that can be applied to the study of functional genomics. This article reviews the methodology involved in array analysis and provides insight into how, as an investigative tool, DNA arrays are becoming increasingly useful in understanding fundamental abnormalities in dermatological disease and also in refining the management of patients with certain skin disorders.