Nb-NHS is a commercially available monomer (although we report its synthesis for the convenience of other researchers) making this approach especially accessible.Nb-NHS is soluble in methylene chloride, enabling us to use our standard polymerization conditions for ROMP. We found that thin films of Nb-NHS could readily be prepared by SI-ROMP. The polymerization yields films up to 45 nm in thickness by ellipsometry. Unmodified poly-NbNHS films have a contact angle of 67 • , similar to the previous report for an acrylic NHS ester polymer but slightly more hydrophobic due to the norbornene hydrocarbon backbone. The polymer reacts efficiently with a primary amine, as reflected in the contact angle of the film before and after functionalization with 1-octadecylamine. (Figure ) After functional-decrease in surface energy. In a previous report by our group, 32 a contact angle in this range (ca 90 • ) corresponded to a near-complete conversion of an NHS ester brush to an octadecyl amide. The poly-NHS-Nb active ester brush is a promising surface functionalization platform for the construction of "molecular wire" type architectures at the surface by the formation of conjugated graft copolymers. Similar brushes have been reported from a living radical polymerization technique which can be quantitatively functionalized using the large aromatic chromophore 1-pyrenemethylamine, an excellent model system for the conjugated aromatic monomers necessary for the formation of conjugated graft copolymers by electropolymerization or metal-mediated coupling. The poly-NHSNb brushes also may be useful for the various other applications of active ester brushes such as microarray-based assays, due to the generally excellent characteristics of the ROMP polymerization. Further work on this system needs to be done in order to determine conditions for end-functionalization of the brush, followed by functionalization of the NHS sidechain with an electropolymerizable system.