We report on the wetting of silica by aqueous solutions of triblock copoly(ethylene oxide-tetrahydrofuran-ethylene oxide), PEO-PTHF-PEO. The wetting behavior was studied by:means of a Wilhelmy force balance and direct images of the contact angle: The results. show that the three-phase contact Line (tcl) advances in jumps over the surface when this Is immersed with constant rate into copolymer solutions. This stick-slip behavior was studied with respect to both the concentration of copolymers in the solution and the immersion rate of the silica plate into the solution. The wetting results are compared with adsorption data obtained by ellipsometry and dynamic Surface tension measurements. It is clear that the stick-slip spreading behavior results from the same basic mechanisms as have previously been proposed for short chain cationic surfactants. The pinning of the contact line is due to the formation (through adsorption) of an autophobic copolymer layer at the solid-vapor interface. At low copolymer concentrations, transport of copolymers to the solid-vapor interface seems to occur mainly through surface diffusion from the liquid-vapor interface to the tcl. Depinning and slip occurs when the dynamic contact angle has increased above a critical value which exceeds that stipulated by the Young's equation in the presence of the autophobic layer at the solid-vapor interface.