In the first part of this article, a comprehensive literature review on hard multilayer coatings, which contain TiN and/or ZrN as a component is given. The developments made in this field, starting with the first published results in 1987 and ending with the latest articles in 2005, were summarized and critically evaluated in order to serve as a starting point for future research in this area. In the second part, recent progress in the nanoscale characterization of multilayers and their interfaces by the small-angle cross-section nanoindentation method and atomic force microscopy is demonstrated on TiN/ZrN multilayers. These nanoscale multilayers were deposited by reactive dc-magnetron sputtering of metallic titanium and zirconium targets in argon/nitrogen plasma onto hard metal and silicon substrates. (c) 2006 American Vacuum Society.