To assess progress in high-temperature calorimetry over the past eighteen years, this feature article discusses both technical developments and new areas of application, with primary emphasis on high-temperature oxide melt solution calorimetry. The Calvet calorimeter for such measurements is now commercially available, and an extensive table of enthalpies of drop solution (sample at room temperature dropped into molten oxide solvent in calorimeter and dissolved) is provided for the user community. New developments in methodology are described and applications to nanomaterials, to nitrides and other monoxide materials, and to lanthanides and actinides are given.