High-frequency distortion in bipolar transistors is examined by using the charge-control approach of Poon and Narayanan (H.C. Poon, IEEE Trans. Electron Dev., vol. ED-19, pp. 719-731, 1972; S. Narayanan and H.C. Poon, IEEE Trans. Circuit Theory, vol. CT-20, pp. 341-351, 1973; H.C. Poon, IEEE Trans. Electron Dev., vol. ED-21, pp. 110-112, 1974) to connect the device's distortion behavior to its "loaded" unity-current-gain frequency (ωˆT). The resulting expressions for the distortion reveal considerable information on its frequency and bias dependence. Points on the ωˆT versus collector current curve yielding optimum distortion performance are identified and interpreted in terms of current cancellation. Both second- and third-order distortion are considered, and the results are validated by both simulation and experiment.