People, as individuals and as speech communities, sometimes change their language deliberately. Deliberate changes are by no means confined to familiar examples of lexical innovations (as in teenage slang and product labeling); they also affect language structure at all levels. Motives for making deliberate structural changes vary, but language or dialect contact is always a factor, except possibly in a few language-planning contexts. Some deliberate changes result from a community’s effort to distance their language from a closely-related language or dialect; another common motive is to withhold the community’s full language from outsiders, as in the case of certain pidgins created by speakers of the lexifier language. This talk surveys these and other motives for making deliberate linguistic changes and considers the potential implications of such changes for theories of language change.