A two-axes MEMS gyroscope system (20, 70) comprising: two proof masses (24, 26); two drive combs configured to drive the proof masses (24, 26) to resonate in plane; two drive sense combs; four Coriolis sense electrodes (63, 40, 42), two of the Coriolis sense electrodes are sensitive to in-plane proof mass motion and two of the Coriolis sense electrodes (40, 42) are sensitive to out-of-plane proof mass motion; a processing device (54, 74) in signal communication with at least one of: the two proof masses; or the four Coriolis sense electrodes; characterised in that bias voltages on the in-plane Coriolis sense electrodes are modulated at a first modulation frequency and the out-of-plane Coriolis sense electrodes are biased at a second modulation frequency; and the processing device (54, 74) includes demodulators that demodulate signals received from the two proof masses or the four Coriolis sense electrodes based onboth of the first and second modulation frequencies, wherein after the processing device (54, 74) demodulates the received signal based on the first frequency, the processing device analyzes the demodulated signal to determine a rate of rotation about the Z-axis, and the processing device demodulates the signals received at the second modulation frequency to determine the rate of rotation about the Y-axis. two proof masses (24, 26); two drive combs configured to drive the proof masses (24, 26) to resonate in plane; two drive sense combs; four Coriolis sense electrodes (63, 40, 42), two of the Coriolis sense electrodes are sensitive to in-plane proof mass motion and two of the Coriolis sense electrodes (40, 42) are sensitive to out-of-plane proof mass motion; a processing device (54, 74) in signal communication with at least one of: the two proof masses; or the four Coriolis sense electrodes; characterised in that bias voltages on the in-plane Coriolis sense electrodes are modulated at a first modulation frequency and the out-of-plane Coriolis sense electrodes are biased at a second modulation frequency; and the processing device (54, 74) includes demodulators that demodulate signals received from the two proof masses or the four Coriolis sense electrodes based onboth of the first and second modulation frequencies, wherein after the processing device (54, 74) demodulates the received signal based on the first frequency, the processing device analyzes the demodulated signal to determine a rate of rotation about the Z-axis, and the processing device demodulates the signals received at the second modulation frequency to determine the rate of rotation about the Y-axis. the two proof masses; or the four Coriolis sense electrodes; characterised in that bias voltages on the in-plane Coriolis sense electrodes are modulated at a first modulation frequency and the out-of-plane Coriolis sense electrodes are biased at a second modulation frequency; and the processing device (54, 74) includes demodulators that demodulate signals received from the two proof masses or the four Coriolis sense electrodes based onboth of the first and second modulation frequencies, wherein after the processing device (54, 74) demodulates the received signal based on the first frequency, the processing device analyzes the demodulated signal to determine a rate of rotation about the Z-axis, and the processing device demodulates the signals received at the second modulation frequency to determine the rate of rotation about the Y-axis.