Recent submicron DC GaAs MESFET models (Ahmed et al., IEEE Trans. Electron. Devices, ED-44 (1997) 360) are improved in order to more accurately facilitate non-linear small-signal circuit designs. The Ahmed-Ahmed-Ladbrooke (AAL) model (Ahmed er al., IEEE Trans. Electron. Devices, ED-44 (1997) 360), allowed for the prediction of the DC characteristics of large-signal submicron devices by using the concept of a shift in threshold voltage. The new model proposed in this paper uses a small number of variables and, while improving on the AAL model. retains the essential form of the more common Curtice and Advanced Curtice models (Curtice, IEEE Trans. Microwave Theory Tech., MTT-28 (1980) 4456: de Graaff and klaassen, Compact Transistor Modelling for Circuit Design, Springer, Vienna, 1990) together with accounting for gate-source voltage modulation effects. (C) 2001 Elsevier Science Ltd. All rights reserved.