The properties of ceramic layers are not only related to the coating material but also—to a very high degree—the processing technology used. In particular, microstructure and thickness are key to the successful implementation of functional layers in application. This will be shown using yttria‐stabilized zirconia (YSZ) as an example, a highly versatile compound with high fracture toughness, high chemical and thermal stability, high biological compatibility, and high oxygen ion conductivity. For each application, specific microstructures are required, which can only be obtained by suitable processing. Herein, coating technologies for layers with thicknesses spanning the nanometer range up to several hundred micrometers, and from full density to tailored open porosity are focused. Wet processing routes, thin‐film deposition from the gas phase as well as thermal and plasma spraying are presented along with the resulting YSZ layers.