This paper presents a straightforward current-mode CMOS squarer circuit. The proposed circuit exploits the square-law characteristic of MOS transistor in saturation region. The squarer circuit is then used to implement multiplier and exponential functions. To demonstrate the method, circuits are designed in 0.35 mu m CMOS process, using single 3.3 V supply. HSPICE simulations, with level 49 model parameters, confirm the operation of the proposed CMOS circuits. Copyright (C) 2010 John Wiley & Sons, Ltd.