Clinical and molecular research aimed to understand glomerular disease has emerged to one of the most active areas in renal research at large. The unraveling of genetic causes resulting in proteinuria has helped to define roles for each component of the glomerular filtration barrier in the development of urinary protein loss. Although most of the inherited glomerular diseases have in common defects in the podocyte, the glomerular basement membrane is also of critical importance for normal kidney permselectivity. This review summarizes recent progress in the eludication of genetic causes of glomerular disease and discusses their implications for the understanding of the pathogenic mechanisms, which can lead to disruption of the glomerular filtration barrier.