A project entitled 'Atom Technology' was initiated in fiscal 1992 for a planned period of 10 years under the MITI sponsored National R&D Program. The 'Atom Technology' project aims at systematically establishing technology for the handling of individual atoms and molecules on a solid surface or in a three-dimensional space, as a generic technology for various fields of industry. This project, closely adjacent to science, emphasizes the following three key focuses: atom manipulation, nanoscale self-organization, and critical-state phase with two basic approaches of in situ dynamical observations (experimental) as well as abinitio calculations (theoretical). In this paper, I pick up several topics From our recent activities in JRCAT and describe some technical details with respect to the above three key focuses. Topics include (1) the removal of an atomic layer from a Si(1 1 1) 7 x 7 surface by scanning tunneling microscope (STM), (2) size-selective growth of SiH cluster ions in a specially designed ion trap, (3) nanoscale wire construction on a Ga-covercd Si(1 1 1) surface in a self-organizing manner, (3) nanometer-scale selective epitaxial growth of Si using a 0.3 nm thick oxide film window, and (5) colossal magneto resistance in perovskite-type manganese oxides.