First principle (ab initio) calculations together with simultaneous thermal analyses and accompanying structural investigations identify cubi (B1, NaCl prototype) CrAlN coatings as promising for high temperature applications. Based on the ab initio data obtained, this is mainly due to small lattice strain and a small electronic driving force for decomposition, which together cause the superior thermal stability of CrAlN as compared to other Al-containing transition metal nitrides. Combining thermal stability with oxidation and corrosion resistance, CrAlN based coatings may hence be useful as protective coatings for delta-TiAl based alloys. Within this scope, the improvement of the oxidation resistance of CrAlN coatings by Y-based reactive element effects and furthermore, the assessment of CrAlYN as protective coating for delta-TiAl based alloys are a focus of this work.