This course is designed to cover the entire geometry processing pipeline based on triangle meshes. We will present the latest concepts for mesh generation and mesh repair, for geometry and topology optimizations like mesh smoothing, decimation, and remeshing, for parametrization, segmentation, and shape editing. In addition to describing and discussing the related algorithms, we will also give valuable implementation hints and provide source code for most of the covered topics. The course assumes only very basic knowledge on geometric concepts in general, but does not require specific knowledge on polygonal meshes and how to discretize the respective problems for those. It is intended for computer graphics researchers, software developers and engineers from CAGD, computer games, or the movie industry, who are interested in geometry processing algorithms based on triangle meshes.