The topics of these papers represent the different perspective in which variation is approached. A number of them represent efforts to analysze and develop the theoretical framework poposed by William Labov and the variation theorists who have followed him. But while most the work in the framework has dealt with phonology and surface syntax, other scholars have begun to investigate variation at deeper syntactic levels, in semantics, and in the conventions of language use. Investigations of these types are also to be found in this collection, as well as studies of variation growing out of language-contact situations and of variation in the sign language used by the deaf.