For mechanically dominated load proAles, nitrides are preferred, while oxide materials oVer better protection against high-temperature corrosion. Thus, when mechanical and thermal loads are combined, the nitrides used should also have excellent temperature and oxidation resistance. How to develop such nitride materials that can withstand both high mechanical and thermal loads will be the focus of this presentation. In addition, we will also discuss the excellent supercapacitor properties of transition metal nitrides. Using transition metal nitride coatings, we will discuss important guidelines for material development to improve strength, fracture toughness, and stability. In particular, the stability (emphasis on phase stability to composition and temperature, but also to oxidation) of nitrides is a highly interesting task. For example, while the face-centered cubic (fcc) structure of TiNx has a relatively large homogeneity range, the fcc structure of other transition metal nitrides (such as MoNx and TaNx) is extremely sensitive to small chemical variations, even if only the vacancy concentration changes. We will use these model systems to explore the possibilities of alloy and structural developments. Among the many alloying elements that have been studied for (Ti,Al)N-based coatings, tantalum is one of the most versatile, capable of simultaneously increasing strength, fracture toughness, thermal stability, and oxidation resistance. This can be further improved when alloyed with Si and reactive elements. The concept of high entropy is also very beneAcial for hard ceramic thin Alms. We will see that, for example, (Hf,Ta,Ti,V,Zr)N and (Al,Cr,Nb,Ta,Ti)N easily outperform their commonly used binary or ternary constituents in terms of thermal stability and thermomechanical properties. In addition, all of the highly entropic ceramic sublattice thin Alms studied were relatively insensitive to variations in deposition parameters-which is good because their properties are at a high level. With superlattice coatings, we will discuss how such nanolamellar microstructures can also simultaneously improve strength and fracture toughness. However, we will also investigate the performance of electrochemical supercapacitors, which strongly depends on chemical stability, accessible surface area, and electrical conductivity. Transition metal nitrides are also excellent candidates for this purpose, but must have a very open-pore microstructure. Glancing angle deposition enables the fabrication of such zigzag-structured electrodes based on γ-Mo2N, combining excellent electrochemical energy storage capabilities with excellent mechanical cexibility. The individual concepts allow the materials to be designed to meet the ever-growing demand for further coatings tailored to speciAc applications.