The integrated structure/control design of flexible robot arms is presented. The open loop, poles, and zeros are relocated by modifying the geometry and the structure of the arm. To determine the geometry and structure in a systematic manner, an inverse mapping method based on finite-element modeling and sensitivity analysis is applied to the flexible arm design. Using this method, a beam geometry that allows for a significantly high natural frequency is obtained. In order to relocate zeros, the torque transmission technique is applied. It makes it possible to remove nonminimum-phase zeros and make the endpoint control robustly stable. Based on the theoretical analysis and computation, a prototype arm was designed and built, and its performance was evaluated.>