The increasing complexity of modern functional materials leads to the demand of acost efficient tool for the development of new products. One possible approach to thisquestion is the adaptation of combinatorial methods to the specific requirements of ma-terials industry. These methods, originally developed for the pharmaceutical industry,have recently been applied to the screening of superconductive, magnetoresistant andphotoluminescent materials. The principle of these combinatorial approaches is thedeposition of large materials libraries in one process combined with fast methods forthe determination of the resulting properties. In this paper, the deposition and charac-terization of laterally graded materials libraries (composition spread) is presented. Thefilms have been deposited by reactive magnetron sputtering, using two or three metallictargets at a low angle to the substrate surface as well as a system of apertures. Toillustrate the advantages of combinatorial approaches for the development of advancedmaterials, the multicomponent metastable hardcoatings (Ti, Al)N and Ti-Al-Si-N arediscussed with special emphasis on the relations between structure and composition onthe one hand and the oxidation resistance of these coatings on the other. The resultsillustrate that the composition spread approach is a powerful and cost efficient tool forthe development and optimization of new multicomponent functional materials.