The precise placement of single-walled carbon nanotubes (SWCNTs) in device architectures by ac dielectrophoresis involves the optimization of the electrode geometry, applied voltage and frequency, load resistance, and type of nanotube sample used. The authors have developed a toolkit to controllably integrate SWCNTs in device structures by the use of floating potential metal posts and appropriate electrode geometries, as designed using electric field simulations, and used it to fabricate structures such as crossed nanotube junctions. (c) 2006 American Vacuum Society.