This text is a rigorous treatment of the basic qualitative theory of ordinary differential equations, at the beginning graduate level. Designed as a flexible one-semester course but offering enough material for two semesters, A Short Course covers core topics such as initial value problems, linear differential equations, Lyapunov stability, dynamical systems and the Poincare-Bendixson theorem, and bifurcation theory, and second-order topics including oscillation theory, boundary value problems, and Sturm-Liouville problems. The presentation is clear and easy-to-understand, with figures and...