Since the discovery of superconductivity in cuprates in 1986, several other classes of high-Tc superconductors (taken to mean Tc >23 K at ambient pressure) have been discovered. Nevertheless this remains a rare property. In this talk the families of known high-Tc materials and their common chemical features will be briefly reviewed and directions for new materials will be considered. Recent results on discovery of new (non-superconducting) transition oxides and nitrides will be presented.