The talk will cover the development of cluster ion beam technology, including historical background, fundamental characteristics of cluster ion to solid surface interactions, emerging industrial applications, and identification of some of the significant events which occurred as the technology has evolved into what it is today. The new ion beam processes, using cluster ions which consist of substantial numbers of atoms or molecules, are very different from those produced by impact of conventional ions comprised of single atoms or molecule. Cluster-surface collisions produce important non-linear effects which are being applied to shallow junction formation, to etching and smoothing of semiconductors, metals, and dielectrics, to assisted formation of thin films with nano-scale accuracy, and to other surface modification applications. Some of the unique industrial applications which have been done by a Japanese large-scale government project (METI/NEDO) will also be presented.