A method of allocating radio frequency spectrum for wireless data transmission to a plurality of wireless data transceivers, the radio frequency spectrum being grouped into sub-ranges and at least one of the sub-ranges of radio frequency spectrum being available for use by said wireless data transceivers, the method comprising: i) notifying the plurality of wireless data transceivers of the availability of the at least one sub-range of radio frequency spectrum and a price for using said at least one sub-range of radio frequency spectrum; ii) receiving requests from at least two wireless data transceivers, each request indicating the number of sub-ranges of radio frequency spectrum required by the respective wireless data transceiver; iii) determining the potential interference that would be caused by the at least two wireless data transceivers being allocated radio frequency spectrum in the at least one sub-range of radio frequency spectrum; iv) calculating a level of demand for the at least one sub-range of radio frequency spectrum in accordance with the requests received from the at least two wireless data transceivers and the determined potential interference; v) modifying the price for using the at least one sub-range of radio frequency spectrum in dependence on the calculated level of demand; vi) sending the modified price for using the at least one sub-range of radio frequency spectrum to the at least two wireless data transceivers; vii) repeating steps i) to vi) until at step iv) the calculated level of demand is less than or equal to the at least one sub-range of radio frequency spectrum; and viii) allocating the at least one sub-range of radio frequency spectrum to the at least two wireless data transceivers in accordance with the determined potential interference, when the calculated level of demand by the at least two wireless transceivers is less than or equal to the at least one sub-range of radio frequency spectrum. i) notifying the plurality of wireless data transceivers of the availability of the at least one sub-range of radio frequency spectrum and a price for using said at least one sub-range of radio frequency spectrum; ii) receiving requests from at least two wireless data transceivers, each request indicating the number of sub-ranges of radio frequency spectrum required by the respective wireless data transceiver; iii) determining the potential interference that would be caused by the at least two wireless data transceivers being allocated radio frequency spectrum in the at least one sub-range of radio frequency spectrum; iv) calculating a level of demand for the at least one sub-range of radio frequency spectrum in accordance with the requests received from the at least two wireless data transceivers and the determined potential interference; v) modifying the price for using the at least one sub-range of radio frequency spectrum in dependence on the calculated level of demand; vi) sending the modified price for using the at least one sub-range of radio frequency spectrum to the at least two wireless data transceivers; vii) repeating steps i) to vi) until at step iv) the calculated level of demand is less than or equal to the at least one sub-range of radio frequency spectrum; and viii) allocating the at least one sub-range of radio frequency spectrum to the at least two wireless data transceivers in accordance with the determined potential interference, when the calculated level of demand by the at least two wireless transceivers is less than or equal to the at least one sub-range of radio frequency spectrum.