A motor control circuit for an electric motor of an electric power assisted steering system of the kind in which a measurement of torque carried by a part of the steering system is used to produce a torque demand signal indicative of a torque to be applied to the steering system by the motor, the control circuit comprising: a switching circuit comprising a plurality of electrical switches (16, 18), a motor current controller that generates voltage demand signals to be passed to a drive circuit for the switches (16, 18) that in turn generates pulse width modulated switching signals for the switching circuit that cause the switches (16, 18) to selectively connect the phases (2, 4, 6) to a power supply so as to cause current to flow through the phases (2, 4, 6) of the motor, in which the current controller is responsive to an error signal that represents the difference between a current demand signal and an actual current signal, and a noise reduction circuit adapted to identify an operating condition of the system in which the motor is stationary or rotating at a very low speed, and characterised in that in the event that the operating condition is identified the noise reduction circuit is adapted to reduce the response of the controller to variations in the error signal. in which the noise reduction circuit includes an attenuator that is adapted to reduce the sensitivity of the controller to changes in the error signal by attenuating the error signal, or filtered error signal, that is fed to the controller with a variable gain when the certain condition is met and in which the variable gain is a function of the magnitude of the error signal, the magnitude of the attenuation being higher for a first error magnitude and lower for a second, higher, error magnitude. a switching circuit comprising a plurality of electrical switches (16, 18), a motor current controller that generates voltage demand signals to be passed to a drive circuit for the switches (16, 18) that in turn generates pulse width modulated switching signals for the switching circuit that cause the switches (16, 18) to selectively connect the phases (2, 4, 6) to a power supply so as to cause current to flow through the phases (2, 4, 6) of the motor, in which the current controller is responsive to an error signal that represents the difference between a current demand signal and an actual current signal, and a noise reduction circuit adapted to identify an operating condition of the system in which the motor is stationary or rotating at a very low speed, and characterised in that in the event that the operating condition is identified the noise reduction circuit is adapted to reduce the response of the controller to variations in the error signal. in which the noise reduction circuit includes an attenuator that is adapted to reduce the sensitivity of the controller to changes in the error signal by attenuating the error signal, or filtered error signal, that is fed to the controller with a variable gain when the certain condition is met and in which the variable gain is a function of the magnitude of the error signal, the magnitude of the attenuation being higher for a first error magnitude and lower for a second, higher, error magnitude.