Perovskite oxides have substantial role in the sustainable energy delivery as reflected by their applicability as oxygen-transporting membranes (OTMs), as electrode/electrolyte components in solid oxide fuel cells (SOFCs), and as OTM-based reactors. These applications represent three major directions that enable the membrane-based oxy-fuel combustion technology, the clean and efficient chemical to electrical energy conversion, and the production of higher value-added chemicals from lower value raw materials. The attractiveness of perovskite oxides arises from the possibility to incorporate different A-site and B-site metal elements into their ABO3-δ lattice to form essentially A1-xA’xB1-yB’yO3-δ compound which allows tailoring of the oxygen non-stoichiometry (and thus the oxygen ionic conductivity), the oxygen reduction reaction activity, and the electronic conductivity to fit a particular application. This paper reviews the basic aspects and progresses in these three directions. The advantages and limitations of perovskites in each application are highlighted and discussed as well as the pertaining aspects.