The question examined here is how a linguistic change takes place in the behavior of the individual speaker. Examples are chosen primarily from lexical change, though phonological and semantic changes are also mentioned. The opinion is expressed that every speaker has a (usually unconscious) norm against which variants operate, change taking place in two steps: (1) when one variant is promoted to tolerated deviation, (2) when a tolerated deviation replaces the earlier norm (called here KYRIOLEXIA in the case of lexical change). The topic of gradual change is also touched upon.