A method of adapting operational radio communication parameters of a small cell base station (30, 320a, 320b) operating to support a small cell (32, 321a, 321b) which overlaps a coverage area (22, 311) supported by a macro cell base station (24, 310), said method comprising: receiving an indication of entry into said small cell of macro cell user equipment communicating with said macro cell base station by detecting an increase in interference in a sub-band of a common radio communication spectrum, said detected increase meeting predetermined threshold criteria indicative of macro cell user equipment entry into said small cell; and if so, adapting said operational radio communication parameters of said small cell base station to move communications between said small cell base station and small cell user equipment away from a sub-band of a shared region of radio communication spectrum common to said small cell base station and said macro cell base station; wherein said adapting comprises: determining said sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station which said macro cell user equipment is using for communication with said macro cell base station and moving any communications between said small cell base station and small cell user equipment away from said determined sub-band to a further sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station. receiving an indication of entry into said small cell of macro cell user equipment communicating with said macro cell base station by detecting an increase in interference in a sub-band of a common radio communication spectrum, said detected increase meeting predetermined threshold criteria indicative of macro cell user equipment entry into said small cell; and if so, adapting said operational radio communication parameters of said small cell base station to move communications between said small cell base station and small cell user equipment away from a sub-band of a shared region of radio communication spectrum common to said small cell base station and said macro cell base station; wherein said adapting comprises: determining said sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station which said macro cell user equipment is using for communication with said macro cell base station and moving any communications between said small cell base station and small cell user equipment away from said determined sub-band to a further sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station. determining said sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station which said macro cell user equipment is using for communication with said macro cell base station and moving any communications between said small cell base station and small cell user equipment away from said determined sub-band to a further sub-band of said shared region of radio communication spectrum common to said small cell base station and said macro cell base station.