Uniform wrapping of a polymers around carbon nanotubes has been recently reported as a means to separate individual nanotubes from their natural bundled state. It has been suggested that polymers wrap the nanotubes in a helical manner due to various interactions, including pi-stacking, hydrophobic and van der Waals. In this communication, we show that surface curvature plays an important role in stabilizing helical conformations. We use Monte Carlo simulations supported by simple thermodynamics arguments to reveal that semi-flexible chains adopt ordered helical conformations at a narrow range of radii, depending only on the stiffness of the chain and cylinder radius. (c) 2006 Elsevier B.V. All rights reserved.