Some embodiments of the present invention provide a proximity sensor (300) comprising: at least a first sensor portion, a second sensor portion and a third sensor portion, the second sensor portion being provided between the first and third sensor portions, the first and third sensor portions each comprising at least a portion of a or a respective substrate (310) having first and second opposite major faces, the first and third sensor portions each bearing on a major face of the or the respective substrate at least a portion of a substantially planar transmit electrode (320), and a substantially planar receive electrode (330A, 330B) arranged to receive a signal transmitted by the respective at least a portion of a transmit electrode, the second sensor portion comprising a first region (315), the sensor comprising a ground shield portion (340) comprising one or more substantially planar, elongate electrodes, the ground shield portion having at least one elongate portion laterally disposed between the receive electrode of the first sensor portion and the first region of the second sensor portion, and at least one elongate portion disposed between the first region of the second sensor portion and the receive electrode of the third sensor portion, the sensor (300) being configured to allow a radio frequency (RF) signal to be applied to the transmit electrode (320) to cause a corresponding RF signal to be induced in each receive electrode (330A-D), the relative strength of the RF signals induced in the receive electrode (330A-D) of the respective portions being responsive to the relative distance of a conducting object therefrom.