A study of overt audible speech behavior in eight male and one female Swedish adults examined the relationship between disfluency and speaking modality, disfluency type in mild versus severe stutterers, and disfluency and psycholinguistic variables. Three conditions of experimental manipulation were used: reading aloud, reading the longer lines of a brief dialogue, and silent reading and oral retelling of a story. The number of disfluencies and stutterings of nine specific types found in taped segments of each condition were tallied. As a group, the subjects showed an increase in disfluency across the three conditions, but individual patterns varied, with the more severely disfluent having unanticipated reduced stuttering in the third, most spontaneous condition. The psycholinguistic variables of grammatical class, word length, phonological position within a word, word position in the phrase, and syllable stress were also examined in the samples, and clear patterns of disfluency appeared in all but the word position variable. It is concluded that varying both speech material and speech tasks was an effective method for elucidation of various speech characteristics in audible speech behavior, highlighting both quantity and quality of speech disruptions and demonstrating differences between mild and severe stutterers. (MSE)