Abstract-The hydrolysis and condensation of organofunctional silanes, Y-(CH2)3-Si(OX)3 (Y = organofunctional group, OX = alkoxy), was studied using time-dependent 29Si-NMR spectroscopy. Data for epoxysilane (DYNASYLAN® GLYMO) are presented. It was found that, on average, 1.5 hydroxyl groups per silicon atom proved to be a limit for the activity of the silane solution in water. In additon, a monomeric aminosilane (DYNASYLAN® AMEO) and monomeric and oligomeric cationic benzylamino-functional silanes (DYNASYLAN® 1161) were applied to E-glass surfaces and the resulting aminosilane films were investigated by AES (Auger Electron Spectroscopy). It was demonstrated that oligomeric cationic aminosilanes exhibited a superior film-formation over commonly used monomeric aminosilanes thus leading to more homogeneous, defect-free silane layers on the E-glass surface.