We demonstrate the use of high index GaAs (41 1)A substrates as templates for the growth of (In,Ga)As quantum wires and quantum dots by molecular beam epitaxy. Scanning tunneling microscopy is used to characterize the facets of these nanostructures. For a deposition of six monolayers of (In,Ga)As on GaAs (4 1 1)A, quantum wire structures were observed to form along the [-122] direction with side facets indexed to 1115 2}. By increasing the (In,Ga)As deposition to twelve monolayers, three-dimensional islands were observed to form above the wires bounded by similar 1115 2} facets as well as steeper {1 10) and (1 11)A facets and a convex curved region composed of (100) facets. (C) 2004 Elsevier B.V. All rights reserved.