The glomerulus, the filtering unit of the kidney, is a unique bundle of capillaries lined by delicate fenestrated endothelia, a complex mesh of proteins that serve as the glomerular basement membrane and specialized visceral epithelial cells that form the slit diaphragms between interdigitating foot processes. Taken together, this arrangement allows continuous filtration of the plasma volume. The dynamic physical forces that determine the single nephron glomerular filtration are considered. In addition, new insights into the cellular and molecular components of the glomerular tuft and their contribution to glomerular disorders are explored.