A method for text-independent speaker identification has been developed which utilizes vowel sounds as the basis for extracting speaker characteristics. Using 63 minutes of conversational speech data from 20 speakers, it was found that vowel recognition is not necessary. Instead, the vowel samples can be pooled such that they represent each person's vowel space, which is expected to be very speaker-dependent. A sequential analysis process has improved the decision procedure by allowing vowel samples to be tested until a specified level of confidence is reached in the identification. This dynamic decision procedure is similar to a human perception process where we can quickly identify a unique voice, but listen longer when there is uncertainty.