A touch-sensitive apparatus, the apparatus comprising: a plurality of drive electrodes, comprising at least a first electrode and a second electrode; at least one receiver electrode; drive circuitry configured to generate a first time-varying voltage signal and a second time-varying voltage signal, wherein the first and second time-varying voltage signals are the inverse of one another; and control circuitry (105, 106) configured to: perform a first measurement on the at least one receiver electrode during a first time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the first time period; perform a second measurement on the at least one receiver electrode during a second time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the second time period; and determine a resultant signal (E 102-1) corresponding to a mutual capacitance between the first electrode and the at least one receiver electrode based on both the first measurement and the second measurement, wherein the plurality of drive electrodes is divided into groups of drive electrodes consisting of N drive electrodes, where N is an even number, and wherein the control circuitry is configured, for each group of drive electrodes, to perform N measurements, including the first and second measurements, over N time periods, wherein for each time period the control circuitry applies at least one of the first time-varying voltage signal and the second time-varying voltage signal to the drive electrodes, and characterized in that, when the plurality of drive electrodes divided by N is not equal to an integer, the control circuitry is configured to include at least one drive electrode in two groups. a plurality of drive electrodes, comprising at least a first electrode and a second electrode; at least one receiver electrode; drive circuitry configured to generate a first time-varying voltage signal and a second time-varying voltage signal, wherein the first and second time-varying voltage signals are the inverse of one another; and control circuitry (105, 106) configured to: perform a first measurement on the at least one receiver electrode during a first time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the first time period; perform a second measurement on the at least one receiver electrode during a second time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the second time period; and determine a resultant signal (E 102-1) corresponding to a mutual capacitance perform a first measurement on the at least one receiver electrode during a first time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the first time period; perform a second measurement on the at least one receiver electrode during a second time period, wherein the control circuitry is configured to supply at least one of the first and second time-varying voltage signals to the first and second drive electrodes during the second time period; and determine a resultant signal (E 102-1) corresponding to a mutual capacitance between the first electrode and the at least one receiver electrode based on both the first measurement and the second measurement, wherein the plurality of drive electrodes is divided into groups of drive electrodes consisting of N drive electrodes, where N is an even number, and wherein the control circuitry is configured, for each group of drive electrodes, to perform N measurements, including the first and second measurements, over N time periods, wherein for each time period the control circuitry applies at least one of the first time-varying voltage signal and the second time-varying voltage signal to the drive electrodes, and characterized in that, when the plurality of drive electrodes divided by N is not equal to an wherein the plurality of drive electrodes is divided into groups of drive electrodes consisting of N drive electrodes, where N is an even number, and wherein the control circuitry is configured, for each group of drive electrodes, to perform N measurements, including the first and second measurements, over N time periods, wherein for each time period the control circuitry applies at least one of the first time-varying voltage signal and the second time-varying voltage signal to the drive electrodes, and characterized in that, when the plurality of drive electrodes divided by N is not equal to an integer, the control circuitry is configured to include at least one drive electrode in two groups.