This book comprises seven chapters. The first chapter addresses a phenomenological approach to the concept 'reaction rate', which views the complex reaction as a single unit whose progress if judged from measurements of the formation rates of the reaction participants; it also sets forth the main strategies by which to determine the rates of heterogeneous catalytic reactions. Another approach, a mechanistic one, relying upon the reaction mechanisms considered in the second chapter that has recourse to the Horiuti-Temkin complex reaction kinetics theory and the elementary statement of the graph method application in chemical kinetics. The third, fourth and fifth chapters consistently expound the philosophy of the steady state multiplicity, auto-oscillations, and the reciprocal effect of competitive catalytic reactions. The sixth and seventh chapters concentrate on the kinetics of some pragmatically important heterogeneous and heterogeneous-homogeneous catalytic reactions. Most results, presented in these chapters were obtained in the authors' laboratories.