Catalytic technologies for converting and reusing CO2 differ from eliminating non-CO2 GHGs (N2O, CH4, fluorocarbons) because they focus on developing cost- and energy-effective catalytic routes for carbon dioxide conversion to usable products. This is a fast-growing area for the crucial relevance of these technologies in closing the carbon cycle in energy and chemical production. Two prominent cases are discussed. The first is when CO2 is used as a reactant to produce added-value chemicals, particularly CO2-containing polymers, where the C-O bonds of the CO2 molecule are not broken. The second case is when renewable energy sources are used to convert CO2. Thus, the main impact is indirect GHG reduction due to the introduction of renewable energy in the value chain. Thus, the general relevance is the possibility of progressively substituting fossil fuels through the so-called solar fuels and chemicals (Solat-to-X technologies), using CO2 to produce energy vectors (to store/transport renewable energy) or to produce chemicals derived from fossil sources. This is the growing area of the so-called Power-to-X processes and, in a longer-term perspective, the so-called artificial leaf devices and Solar-to-X technologies. However, passing directly to the latter is desired. It is possible to distinguish between first-generation approaches, which are already in a pilot stage or even higher stage of development and are based on the use of thermal catalysis in the step of CO2 conversion, and second-generation processes, based on photo- or electro-catalytic conversion of CO2 and which thus allow a more direct and energy-efficient link with the use of renewable energy sources.