A two-dimensional position sensor is formed by drive electrodes (52) and sense electrodes (62, 64, 66) both extending in the x-direction and interleaved in the y-direction. The sense electrodes comprise several groups, two of which co-extend in the x-direction over each different portions of extent in the x-direction. The drive and sense electrodes are additionally arranged to capacitively couple with each other. In use, drive signals are applied to the drive electrodes and then the resultant sense signals received from the sense electrodes measured. The position of a touch or stylus actuation on the sensor is determined in the x- and y-directions as follows. In the x-direction, the position is determined by an interpolation between sense signals obtained from co-extending pairs of sense electrodes, and in the y-direction by interpolation between sense signals obtained from different sequences of drive signals applied to the drive electrodes.