Optical manipulation of nano- and micro-scale particles via optical tweezers and optical landscapes continues to be of great interest in several fields, reflected by the myriad experimental pursuits suggesting selective and parallel control over particles of anisotropic shape (blood cells, nanorods, etc.). Our work here approaches the goal of a complete model of these phenomena by means of optical scattering principles and, specifically, the T -matrix method. Here we describe the salient features of our model, which tends toward a complete and consistent modeling scheme for determining the behavior of dielectric, polarizable, mesoscale particles of anisotropic shape in arbitrary intensity gradients. We explore forces and torques caused by periodic optical landscapes as well as torques induced by the polarization orientation of the electric field.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.