This paper illustrates how the sociolinguistic concept of code switching applies to the use of different styles of music. The two bases for the analogy are Labov's definition of code-switching as "moving from one consistent set of co-occurring rules to another," and the finding of sociolinguistics that code switching tends to be part of communicative strategy. At least two types of codes or styles seem to exist in music, diachronic and synchronic. Diachronic style pools exist in both classical and contemporary popular music. In many current sound recordings, both the past and present styles of music are incorporated in the same piece. Performers of contemporary music have to alternate styles to suite their audience. Another mode of code-switching is the superimposition of two sets of words on the same musical score. Three types of "ethnic code-switching" are apparently close to the concern of sociolinguistics. These are: (1) accomodation of the music to ethnically mixed audiences; (2) accomodating a minority culture's traditions to a mainstream musical piece; and (3) musical change brought about by contact between cultures. While many questions are left untouched, it is indicated that the analogies could lead to joint exploration of musical material by both ethnomusicology and sociolinguistics. (AMH)