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Materials’ requirements in the world of electronic devices are rapidly expanding towards their multi-functionality, their integration onto reactive substrates, the use of environmentally friendly raw materials and processes, reduced levels of energy consumption and their high efficiency. This is reflected in the search for ceramic materials with excellent, reproducible and stable functional properties obtained via energy-efficient processing. While chemical composition of perovskite ferroelectrics determines their symmetry and phase transitional behavior, and consequently their physical properties, tuning of properties may be achieved by doping strategies. As revealed decades ago, microstructural design is another critical factor which contributes to tailoring the functional properties of ferroelectrics. The choice of the processing route and related shape – bulk ceramic, multilayer, thick or thin film – contributes to the stoichiometry and defect chemistry, and importantly tailors the microstructural features down to nm-scale. While thermal energy has been for ages the main driving force for consolidation of ceramics, emerging low-temperature routes such as cold sintering and aerosol deposition offer a new perspective on the evolution of the microstructure and defect chemistry in non-equilibrium conditions. The focus of this contribution is on reexamination of classical processing-microstructure-properties relationships for selected ferroelectric and relaxor-ferroelectric ceramic materials. Case studies of sodium potassium niobate-based piezo-/ferroelectrics, and lead-based relaxor-ferroelectrics for electrocaloric applications will be discussed.