Book excerpt: The book gives a novel treatment of recent advances on constrained control problems with emphasis on the controllability, reachability of dynamical discrete-time systems. The new proposed approach provides the right setting for the study of qualitative properties of general types of dynamical systems in both discrete-time and continuous-time systems with possible applications to some control engineering models. Most of the material appears for the first time in a book form. The book is addressed to advanced students, postgraduate students and researchers interested in control system theory and optimal control.