With linguistics suffering from increasing fractionalization, it is necessary not to lose sight of the overall picture. It seems uncontroversial that the study of language consists of the following five components: processing, use, structure, variation, and change. While some of the relationships between these concepts have been investigated, a systematic integration of these components into a coherent framework is conspicuously missing. A modest attempt is made here to outline such a framework which makes the interrelationships of the components transparent. In all of these components, competition is found to play a key role. At its core, competition is a psycholinguistic effect which arises in the task of selecting an intended unit from among a number of elements concurrently activated in the processing network. The audible and visible outcome of the selection process is language use. Language structure is the prerequisite for competition in that it provides the set of competitors. When competition is low, consistent (i.e., invariant) language use emerges. When competition is high, language use is variable, i.e., synchronic variation occurs. When competition changes over time, language change takes place. Thus, it is language processing in general and competition in particular that constrains and binds together many phenomena of language use, structure, variation, and change.