Solid-state mechanochemical processing of nanomaterials offers unique opportunities for the creation of value-added materials. The present review reexamines physicochemical aspects of these processes and identifies the merits of leveraging local deformation derived phenomena such as symmetry loss of ligand field, charge-transfer across the grain boundary, reaction-induced amorphization and the consequences of intimate mixing for the creation of new materials. Case studies are also presented that include ligand exchange of transition metal coordination compounds, anion substitution of metal oxides, organic synthesis and drug amorphization. All these studies provide promise for solid-state mechanochemical processing in the future as a cornerstone of powder technology. (C) 2010 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.