Dynamical systems theory in mathematical biology has attracted much attention from many scientific directions. The purpose of this volume is to present and discuss the many rich properties of the dynamical systems that appear in life science and medicine. The main topics include cancer treatment, dynamics of paroxysmal tachycardia, vector disease model, epidemic diseases and metapopulations, immune systems, pathogen competition and coexistence and the evolution of virulence and the rapid evolution of viruses within a host. Each chapter will serve to introduce students and scholars to the state-of-the-art in an exciting area, to present new results, and to inspire future contributions to mathematical modeling in life science and medicine.