We report on the growth of surface-bound, vertically oriented one-dimensional III/V nanostructures, specifically GaAs and InAs nanowires, on lattice-matched and -mismatched substrates by selective-area vapor-phase epitaxy. Control of nanowire features and growth directions is achieved by tuning the growth conditions. Grown nanostructures are characterized by scanning and transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. (C) 2009 The Electrochemical Society. [DOI:10.1149/1.3222852] All rights reserved.