Nanotechnology is almost a household word now-a-days, or at least some word with ‘‘nano’’ in it, such as nanoscale, nanoparticle, nanophase, nanocrystal, or nanomachine. This field now enjoys worldwide attention and a National Nanotechnology Initiative (NNI) is about to be launched. This field owes its parentage to investigations of reactive species (free atoms, clusters, reactive particles) throughout the 1970s and 1980s, coupled with new techniques and instruments (pulsed cluster beams, innovations in mass spectrometry, vacuum technology, microscopes, and more). Excitement is high and spread throughout different fields, including chemistry, physics, material science, engineering, and biology. This excitement is warranted because nanoscale materials represent a new realm of matter, and the possibilities for interesting basic science as well as useful technologies for society are widespread and real.