ferring to activities in which the research of sociolinguists is employed (very often by sociolinguists themselves) in other fields where it can be of some value. In some cases sociolinguistic research (unlike, say, research in theoretical syntax) has been carried out with an avowedly practical purpose. In other cases, sociolinguists have found themselves involved in "applying" their findings, if not exactly against their will, at least without initially intending that they should be used in this way. One area of sociolinguistic work of which this has undoubtedly been true is "secular linguistics". Following Labov's lead in this field, large amounts of often very exciting work have been carried out in the form of empirical studies of language as it is spoken in its social context. Research of this type has been aimed principally at improving linguistic theory, and acquiring a better understanding of the nature of language variation and the sources of linguistic change. However, the results of Labov's work, and that of his followers, were very rapidly, from the 1960s onwards, applied in a highly significant way to two different but related educational problems: the debates concerning non-standard (especially American Black English) dialects in education; and so-called "verbal deprivation" or "language deficit". In the first of these debates, it was the sociolinguists' increased understanding of linguistic variation and their phonological and grammatical descriptions of non-standard dialects that became important. In the second, on "verbal deprivation", one crucial factor proved to be the large amounts of spontaneous, relatively unmonitored, casual speech recorded by sociolinguists concerned to overcome the "observer's paradox". In the present volume, the chapter by J. Milroy, on "Sociolinguistic methodology and the identification of speakers' voices in legal proceedings" exemplifies a new use for quantitative studies of the Labovian type: the employment of sociolinguistic findings in a field we can perhaps call "forensic sociolinguistics". And in another examination of the uses of work of this type, Fasold, in his chapter on language learning, looks at the application of variation theory, a relatively recent theoretical development out of Labovstyle secular linguistics. His chapter uvariation theory and language learning" starts from attempts to incorporate sociolinguistic findings concerning the structure and probabilistic nature of linguistic variation into theoretical models, and links these to foreign language acquisition processes. This book, however, is not only concerned with the applications of secular linguistics. We are concerned also with the Jess than purely linguistic forms of sociolinguistics, such as the social psychology of language; the ethnography of speaking; the sociology of language; and discourse analysis. The social psychology of language is an area of study which deals with attitudes to varieties of language, and with the way in which speakers interact with each other through conversation. Clearly, its range of potential applications is