Nitroxide-mediated polymerization (NMP) has proven to be powerful and versatile approach for designing polymers with tailored molecular weights, compositions, and microstructures, but NMP has also proven to be readily adaptable for modifying a range of different solid surfaces using a technique known as surface-initiated nitroxide-mediated polymerization (SI-NMP). In SI-NMP a suitable initiating moiety is first bound to a chosen surface and then using conditions similar to NMP, a polymer chain is grown from the surface in a procedure often referred to as grafting from. SI-NMP has been applied to both flat surfaces and particles ranging in size from tens of nanometers to several microns. The nature of the substrate can be inorganic, metallic or polymeric including both synthetic and natural polymers. Because SI-NMP allows facile precision synthesis of polymers at high chain densities, this approach has been widely used in polymer brushes and other fields where it is desirable to modify only the surface properties of a material while preserving its bulk properties. This chapter presents the fundamental concepts of SI-NMP and the structure/properties of polymer brushes, and reviews recent progress in SI-NMP. The importance of SI-NMP to the fields of nanoscience and nanotechnology will be evident, in addition to the potential role of SI-NMP in other areas of application, including composites and advanced materials.