We present a strategy to control the chirality of single-walled carbon nanotubes synthesized by chemical vapor deposition (CVD) over crystalline catalyst nanoparticles. Atomic-resolution imaging of nucleation points makes it possible to explore the structural correlation between the catalysts and the corresponding nanotubes. The formation of nanotubes with specific chirality could be associated with the angle of the step edge on (111) plane of the particle with respect to the growth direction of nanotubes. The result shows the potential in promoting some experimental advances in synthesis of nanotubes with the desired structure. (C) 2008 Elsevier B.V. All rights reserved.