A great deal of recent research has focused on phonetic variation among American English vowels from different dialects. This body of research continues to grow as vowels continuously undergo diachronic formant changes that become characteristic of certain dialects. Two experiments using the Nationwide Speech Project corpus (Clopper & Pisoni 2006a) explored whether the Midland dialect is more closely related acoustically and perceptually to the Mid-Atlantic or to the Southern dialect. The goal of this study was to further our understanding of acoustic and perceptual differences between two of the most marked dialects (Mid-Atlantic and Southern) and one of the least marked dialects (Midland) of American English. Ten vowels in /hVd/ context produced by one male talker from each of these three dialects were acoustically analyzed and presented to Midland listeners for identification. The listeners showed the greatest vowel identification accuracy for the Mid-Atlantic talker (95.2%), followed by the Midland talker (92.5%), and finally the Southern talker (79.7%). Vowel error patterns were consistent with vowel acoustic differences between the talkers. The results suggest that, acoustically and perceptually, the Midland and Mid-Atlantic dialects are more similar than are the Midland and Southern dialects.