Much of modern spectrum management is based on an implicit assumption that the applications that share a particular portion of spectrum will have broadly similar characteristics and deployment. However, the ever-widening range of uses of the radio spectrum means that this is often no longer the case. A similar situation arises when licence-exempt spectrum is used in novel ways. An example of this is the 60GHz band. Does the approach to studying coexistence need to change, or are we heading towards increasing problems of interference between dissimilar applications? Simon will suggest a possible approach to mitigate this interference, by recommending ‘default’ frequencies to be used by an application in the absence of other users or interference. The ‘default’ frequency would be different for different applications, which would reduce ‘clashes’ between different types of use.