Reverse Engineering in Control Design presents a variety of practical approaches for building a standard H problem, taking into account an initial controller. These approaches facilitate the mixing of various control objectives as well as the initialization of procedures for fixed-structure controller design. They are based on the Observer-Based Realization (OBR) of controllers. The discussion of OBR from the controller implementation point of view is detailed and highlighted with academic examples. An open-source toolbox is available for readers wishing to implement these approaches in MATLAB.