MINOPT is a comprehensive, powerful, and flexible package for the solution of various types of optimization problems. It features both an advanced modeling language for the clear and concise representation of complex mathematical models as well as robust algorithmic framework for the efficient solution of wide variety of mathematical programming problems. MINOPT was developed in the CASL laboratory in the Department of Chemical Engineering at Princeton University. It’s development has been motivated by the need for efficient methods for solving Mixed-Integer Nonlinear Programming problems as well as handling numerous options associated with these problems. Further development was motivated by the need to handle dynamic models and solve problems involving both differential and algebraic constraints. The result is an advanced modeling language and algorithmic framework.