Metal-organic Frameworks (MOFs) and Covalent-organic Frameworks (COFs) are non-conventional porous materials based on the self-assembly of organic/inorganic and organic/organic prearranged synthons, respectively. The extensive library of synthons and synthetic conditions can lead to the formation of a wide variety of MOFs and COFs with functional properties – adsorption, separation, capture, heterogeneous catalysis, sensing, drug delivery, to quote a few – that outperform, in many aspects, those of classical porous materials.