In many technical applications materials have to be coated or joined by adhe-sive technology. However, due to their non-polar surface properties common polymers such as polyolefines cause difficulties in coating and bonding pro-cesses. Moreover, the non-reactive surface of poylolefines also renders a selective functionalization difficult. Today, several physical and chemical processes are known to activate polymer surfaces prior to use. Plasma and corona modification techniques (i.e. physico-chemical surface treatments) are ecologically more acceptable than chemical etching processes e.g. with oxidizing agents. In this work, linear low-density polyethylene (LLDPE) was modified with plasma- and corona processes under oxygen atmosphere. The effects of both treatments on the surface properties of LLDPE were studied and compared to each other. The activated surfaces were chemically unified by a reductive treatment with lithium aluminium hydride. To assess the efficacy of the activation and unification process, the reaction with perfluorinated acyl chlorides was used as a probe. In all cases, X-ray photoelectron spectroscopy (XPS) was employed as analytical technique to determine the elemental composition of the modified polymer surface. Moreover, a graft-copolymerization of norbornenedicarboxylic acid, dimethyl ester, onto the activated LLDPE surface was successfully performed and covalently bound surface coatings were obtained.