Stutterers sometimes report that by exerting articulatory pressure they can force themselves to have “real” blocks. A procedure was devised for instructing subjects to force stuttering under various conditions and for recording their introspections. Most subjects were able to force at least a few blocks which they regarded as real. Most of the words on which the attempts were said to succeed were feared or difficult words, and at times subjects assisted the process by “telling” themselves that they would not be able to say the word. Fewer subjects were able to force blocks on isolated sounds than on words, and almost none claimed to succeed on mere articulatory contacts. Subjects repeatedly characterized “real” stuttering as involving feelings of physical tension and loss of control over speech. The nature of the forced block is discussed with reference to a concept of stuttering as a struggle reaction which has acquired a high degree of automaticity.