We review recent reports of solvothermal or hydrothermal procedures for the preparation of isolated nanoparticles of some important oxide and chalcogenide materials. The synthetic procedures listed here have the advantages of being relatively inexpensive in terms of the solvents used, arguably green (when water is the solvent) and amenable to scale-up. Handling or processing under inert conditions are rarely called for. We include descriptions of work involving the preparation of capped quantum dots using solvothermal techniques as well as microwave-hydrothermal routes and flow-hydrothermal routes that allow continuous and rapid processing of nanoparticulate materials.