In this article, we discuss a few recent advances in fabrication and application of highly ordered nanopost arrays. These arrays are vertically aligned and are uniform in diameter, height, and spacing. They can be made from a large variety of materials ranging from metals, semiconductors, and carbon nanotubes. The keys to achieving a high degree of uniformity and ordering are in the formation and the use of a highly ordered nanopore array as a growth template or mask. The uniformity and vertical orientation greatly facilitate the use of these arrays in biomolecular interfacing, field (optical and acoustic) sensing and modulation, as well as field emitters. (c) 2006 American Vacuum Society.