In the present paper, the redesign of a transonic rotor was performed by means of a three-dimensional viscous inverse design method. The inverse approach used in this work is one where the pressure loading, blade thickness distribution and stacking axis are specified and the camber surface is calculated accordingly. The design of transonic and supersonic axial compressors strongly relies on the ability to control the shock strength, location and structure. The use of an inverse design method allows one to act directly on aerodynamic parameters, like the blade loading, and provides an efficient tool to control the shock wave and its interaction with the boundary and secondary flows and with the tip clearance vortex. In the present study, the parametric investigation of the blade loading distribution was carried out. Few design parameters, with immediate physical meaning, were required to control the three-dimensional blade loading, and their impact on the design and off-design performance of the rotor was assessed by means of CFD calculations. Further investigations were then performed in order to study the impact on the rotor performance of the geometrical parameters (meridional channel and thickness distribution), which must be imposed in the design with the inverse method. As a result, it was possible to develop guidelines for the aerodynamic design of transonic rotors that can be exploited for similar design applications.Copyright © 2007 by ASME