William Labov (born December 4, 1927) is a professor in the linguistics department of the University of Pennsylvania. He is widely regarded as the founder of the discipline of quantitative sociolinguistics and pursues research in sociolinguistics and dialectology.
Born in Rutherford, New Jersey, he studied at Harvard (1948) and worked as an industrial chemist (1949-61) before turning to linguistics and taking his PhD at Columbia University (1963). He taught at Columbia (1964-70) before becoming a professor of linguistics at the University of Pennsylvania (1971), and then became director of the university's Linguistics Laboratory (1977). The methods he used to collect data for his study of the varieties of English spoken in New York City, published as The Social Stratification of English in New York City (1966), have been influential in social dialectology. In the late 1960s and early 1970s, his studies of the linguistic features of Black English Vernacular (BEV) were also influential: he argued that BEV should not be stigmatized as substandard but respected as a variety of English with its own grammatical rules, although speakers of BEV should be encouraged to learn standard American English for interactions in society at large. He is also noted for his seminal studies of the way ordinary people structure narrative stories of their own lives. His works include Language in the Inner City: Studies in Black English Vernacular (1972), Sociolinguistic Patterns (1972), and Principles of Linguistic Change (1994).