Polymeric coatings, usually referred as tridimensional chemistries, provide homogenous surface derivatization methods presenting a high reactive group concentration and resulting in an increased binding capacity of targets. Furthermore, they act as linkers distributing the bound probe also in the axial position, thus causing a faster reaction with the target involved in biomolecular recognition and can be engineered to custom tailor their properties for specific applications. Most approaches which aim at attaching polymers to a surface use a system where the polymer carries an "anchor" group either as an end group or in a side chain. This anchor group can reacts with appropriate sites at the substrate surface, thus yielding surface-attached monolayers of polymer molecules (termed "grafting to"). Another technique is to carry out a polymerization reaction in the presence of a substrate onto which monomers had been attached leading to the so called "grafting from" approach. In this chapter, protocols to functionalize glass and silicon surfaces by "grafting to" as well as by "grafting-from" approach are shown using copolymers made of N,N-dimethylacrylamide (DMA) or Glycidyl methacrylate (GMA) as the polymer backbone, N-acryloyloxysuccinimide (NAS) as reactive group, and 3-(trimethoxysilyl)propyl methacrylate (MAPS) or 3-mercaptopropyl trimethoxy silane (MPS) as anchoring groups.