This study compares the pronunciation of the stressed vowel nuclei of black and white southerners interviewed for the Linguistic Atlas of the Middle and South Atlantic States. The informants from Maryland (two pairs), Virginia (seven pairs), and North Carolina (seven pairs), were all interviewed in the period 1933-1939 by a single field worker, Guy S. Lowman, Jr., and were matched as closely as possible for age, education, social class, and geographical proximity. The principal findings of the study are that systematic differences exist between black and white speakers in the pronunciation of the stressed vowels, on the phonic or subphonemic level. This is the same type of variation that is used to characterize dialect differences in the United States. The differences in speech, however, while systematic, are not categorical: i.e., there are no speech features examined that exist solely for black or white speakers. Another finding was that regional variation in speech was less apparent for black speakers than for white speakers.