Over the last 5 to 10 years, basic research in the areas of cell biology, biochemistry, immunology, and molecular biology has led to quantum advances in our understanding of the causes of the bullous diseases. This explosion of new information has been made possible by corresponding technologic advances related to these scientific disciplines. This article does not represent a comprehensive review of this topic, but rather highlights important contributions primarily from the field of molecular biology. Much of this article describes research technologies aimed at identifying and characterizing the genes and gene products that are directly involved in the pathogenesis of the bullous disorders. Although many significant advances have been made, a great deal remains to be done. It is our hope that the next 5 to 10 years will witness the emergence of a new set of technologies that will facilitate the translation of this new-found molecular information into more accurate diagnostic tools, more effective therapeutic strategies, and a fuller understanding of the basic biology of the skin.