PoLAR (Portable Library for Augmented Reality) is a framework which aims to help creating applications for augmented reality, image visualization and medical imaging. PoLAR is designed to offer useful tools without the need to be a specialist of them. The framework offers the necessary tools to create graphical applications. They are designed to be easy to use and as complete and powerful as possible. The framework is written in C++ and published under the GNU GPL license.