A method of switching data packets between an input and a plurality of outputs of a switching device. The switching device comprises a memory arranged to store a plurality of data structures, each data structure being associated with one of said outputs. The method comprises receiving a first data packet at said input, and storing said first data packet in a data structure associated with an output from which said data packet is to be transmitted. If said first data packet is intended to be transmitted from a plurality of said outputs, indication data is stored in each data structure associated with an output from which said first data packet is to be transmitted, but said first data packet is stored in only one of said data structures. The first data packet is transmitted from said data structure to the or each output from which the first data packet is to be transmitted.