An ion trapping system comprising: a plurality of electrodes (2,3;5,6); one or more voltage supplies connected to the electrodes, wherein the electrodes and the one or more voltage supplies are adapted and configured to provide an ion trapping region configured to trap ions in three dimensions in use; an ion entrance for receiving ions into the ion trapping region along an ion entrance axis, in use; an ion ejecting system for ejecting ions from the ion trapping region along an ion exit axis in use, wherein the electrodes and voltage supplies are configured such that the maximum dimension over which the ion trapping region extends orthogonal to the entrance axis and/or exit axis is greater than the maximum dimension over which the ion trapping region extends parallel to the entrance axis and/or exit axis; and further comprising one or more of the following: (i) an ion urging system for urging ions within the ion trapping region orthogonally to the entrance and/or exit axis so that the ions spread out within the ion trapping region, wherein the ion trapping region is adapted and configured to be maintained at a pressure of ≥ 0.01 mbar; and/or (ii) an ion deflector arranged upstream of the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards the ion trapping region such that ions entering the ion trapping region enter the ion trapping region at different locations; and/or (iii) an ion deflector arranged upstream of, or at the entrance to, the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards or into the ion trapping region such that ions enter the ion trapping region with different speeds orthogonal to the exit axis and/or the entrance axis so that the ions spread out within the ion trapping region in a direction orthogonal to the entrance axis and/or exit axis. a plurality of electrodes (2,3;5,6); one or more voltage supplies connected to the electrodes, wherein the electrodes and the one or more voltage supplies are adapted and configured to provide an ion trapping region configured to trap ions in three dimensions in use; an ion entrance for receiving ions into the ion trapping region along an ion entrance axis, in use; an ion ejecting system for ejecting ions from the ion trapping region along an ion exit axis in use, wherein the electrodes and voltage supplies are configured such that the maximum dimension over which the ion trapping region extends orthogonal to the entrance axis and/or exit axis is greater than the maximum dimension over which the ion trapping region extends parallel to the entrance axis and/or exit axis; and further comprising one or more of the following: (i) an ion urging system for urging ions within the ion trapping region orthogonally to the entrance and/or exit axis so that the ions spread out within the ion trapping region, wherein the ion trapping region is adapted and configured to be maintained at a pressure of ≥ 0.01 mbar; and/or (ii) an ion deflector arranged upstream of the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards the ion trapping region such that ions entering the ion trapping region enter the ion trapping region at different locations; and/or (iii) an ion deflector arranged upstream of, or at the entrance to, the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards or into the ion trapping region such that ions enter the ion trapping region with different speeds orthogonal to the exit axis and/or the entrance axis so that the ions spread out within the ion trapping region in a direction orthogonal to the entrance axis and/or exit axis. (i) an ion urging system for urging ions within the ion trapping region orthogonally to the entrance and/or exit axis so that the ions spread out within the ion trapping region, wherein the ion trapping region is adapted and configured to be maintained at a pressure of ≥ 0.01 mbar; and/or (ii) an ion deflector arranged upstream of the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards the ion trapping region such that ions entering the ion trapping region enter the ion trapping region at different locations; and/or (iii) an ion deflector arranged upstream of, or at the entrance to, the ion trapping region, wherein the ion deflector is configured to deflect at least some of the ions travelling towards or into the ion trapping region such that ions enter the ion trapping region with different speeds orthogonal to the exit axis and/or the entrance axis so that the ions spread out within the ion trapping region in a direction orthogonal to the entrance axis and/or exit axis.