The research addresses control design for mechanical systems. Specifically, the intent is the development of a highly transparent practical design methodology for the synthesis of robust controllers for mechanical systems, systems often characterized by nonlinear differential equations and such phenomena as friction, saturation, dead zones, backlash and hysteresis. The methodology to be developed parallels Quantitative Feedback Theory and is based on frequency domain design tools. Unlike recent new theories of robust control which have emphasized mathematical elegance at the expense of practical design tools, the proposed work has an engineering style and is aimed at developing a realistic, easy to use design tool. The research entails both theoretical and experimental work and will include a number of simulation case studies.***//