Adaptive control of operating and body bias voltages. In accordance with a first embodiment of the present invention, a desirable operating frequency for the microprocessor is determined. Information stored within and specific to the microprocessor is accessed. The information can comprise coefficients of a quadratic approximation of a frequency-voltage characteristic of the microprocessor for a set of body biasing conditions. An efficient voltage for operating the microprocessor at the desirable operating frequency is computed. The microprocessor is operated at the efficient voltage and the set of body biasing conditions.