Decentralized stable factors (DSF) am used to extend the stable factorization approach to the design of decentralized controllers. The DSF allow a parameterization of all the stabilizing decentralized controllers in the form of a Youla parameterization. A decentralized controller serves as the central controller, and the Youla parameter has a particular and must satisfy an interaction constraint. This parameterization encompasses several other parameterization results on decentralized control systems.