The ethnography of communication, particularly of greetings, among speakers of some Yoruba dialects is the major concern of this paper. The author observed that the much-cherished, rich culture of greetings, among Yoruba, which the author grew up to know, is fast being eroded by linguistic globalization and modernization. The study and documentation of the sociolinguistic structure of greetings are both anthropological and ethnographic because greetings, as part of Speech Act, belong to the domain of language and culture. Describing language behavior observed daily in different cultures is the purview of an ethnographer. A detailed comparison of greetings among speakers of three Yoruba dialects (Igbomina, Ijesa, Ijebu) can no longer be regarded as a compulsive desideratum, because documentary linguistics is now seen as a salvage work. Our work is therefore that of data collection, organization, transcription, translation and interpretation of the morpho-syntax and semantics of greetings in the three dialects. The rationale for the study is based on our belief that since language is rooted in a speech community, in its history and culture, each language or dialect is unlike any other language, hence no data can be regarded as the same. By the same token, linguistic data are not easily replicable. Because data from extinct dialects are not easily replaceable, documenting greetings in these dialects will make them accessible to others, thus saving them from gradual extinction.