A research project was aimed at measuring the relationship between infant vocalizations and linguistic development and determining the feasibility of using infant vocalizations as a predictor of later psychological and intellectual status. However, a method was needed to analyze the vocalizations of infants. This report describes a method used to analyze the vocal behavior of infants in their prelinguistic stage, from birth to 4 months. The method was based on the "distinctive features" concept. Eight distinctive features of infant vocalization were coded by observers. This data yielded information on the quality and frequency of infant vocal behavior and provided a measure of individual differences between prelinguistic infants. Data have been collected on forty 3-day-old infants. This eight-feature coding scheme has proven to be reliable. (WD)