‘Special reduction’ refers to instances of extreme phonetic reduction which is restricted to particular words or phrases, usually grammaticalizing constructions (going to > [gə̃ɾ̃ə̃]), greetings (hi from how are you), discourse markers (Spanish o sea > sa), or other sequences that are often used together. On the basis of data from English, Brazilian Portuguese, and Colombian Spanish, we argue that special reduction is based on the general phonetic tendencies in the language, but that these tendencies are carried to an extreme where word sequences are used with high frequency and become chunked, allowing formerly stressed syllables to lose stress and reduce. The data also show that special reduction takes place gradually over time, and reflects general patterns of change seen in the history of the language. In fact, in some examples, special reduction presages more general sound changes that occur later. We argue that the gradual phonetic changes that accumulate for particular words or phrases, eventually changing them dramatically, requires an exemplar model for the phonological representation of words and phrases, which is updated continually as sequences are used and affected by reductive phonetic processes.