A method of allocating a channelisation code to one of a plurality of user terminals for decoding of signals sent according to a code division multiple access scheme is provided. The plurality of user terminals being reserved the code for possible use. The method comprising selecting according to a predetermined rule the user terminal to which the code is to be allocated, and allocating the code to the selected user terminal, in which the plurality of user terminals having the code for possible use constitute a group, and there are multiple groups of terminals each having an associated unique code, a record is kept of which user terminals are in which group, and the user terminal to which the code is to be allocated is selected following inspection of the record to determine which user terminals are in the group associated with the code.