Provides a general framework useful for the application of the theory of ODEs, as well as a sophisticated use of Mathematica software for the solution of problems related to ODEs. Through extensive worked examples and computer program demonstrations using Mathematica, the authors cover phase portrait, approximate solutions, periodic orbits, stability, bifurcation, and boundary problems. For graduate students, researchers, and practitioners in applied mathematics and engineering seeking an understanding of using ODEs in modeling physical, biological, and economic phenomena.