This paper presents a methodology for designing piezoelectric sensors/ actuators in an application to monitor/generate flexural and torsional vibrations of cylindrical Shells. Based upon the classical laminate theory the equations of the electro-mechanical interactions, the constitutive, and the strain-displacement relations of piezoelectric composite cylindrical shells are derived. With these relations the piezoelectric sensor and actuator equations of the cylindrical shell are then developed. The modal sensors/actuators fabricated with PVDF embedded in the composite cylindrical shell capable of monitoring and generating vibrations of a particular mode or several combined modes are also developed. Finally, an experimental rig is designed to generate both the flexural and the torsional vibrations of a. circular cylindrical shaft for examining the capabilities of the modal sensors.