A survey and analysis of the 2.4 GHz ISM band has been carried out in order to assess the occupancy of this band by a range of services. Both the time-varying nature of usage and the density of users in the areas covered were assessed. The sites surveyed included private sector, public sector and city centre locations. The study concluded that the use of 2.4 GHz services appears to be very widespread. Generally, the recorded levels of activity were low. An instance of WLAN interference, due to microwave detectors operating legitimately in the 2.4 GHz band, was observed. This and subsequent studies will be used to inform the spectrum management process in this and other bands where WLANs are being deployed.