Many interesting economic models cannot be solved analytically using the standard mathematical techniques. Nonlinear stochastic optimal control problems and nonlinear dynamic tracking games are two research areas where this problem occurs frequently and which are discussed in this work. This book gives some insight into these frameworks, both on the theoretical basis and giving application examples. From the theoretical point of view, this book describes both frameworks and presents two numerical methods designed to solve such problems. The algorithm OPTCON2 is designed for solving nonlinear stochastic optimal control problems. The algorithm OPTGAME3 is designed for solving nonlinear dynamic tracking games. The application part of the book gives several examples of using these frameworks for economic problems. The present work is oriented at readers which are mainly interested in research. As such the book is aimed at graduate students and researchers mainly, but not only in economics.