Conditional discrimination is inherent in the intraverbal relation when one verbal stimulus alters the evocative effect of another verbal stimulus and they collectively evoke an intraverbal response. Rarely in research on conditional discriminations have both conditional and discriminative stimuli been vocal verbal and rarely have the responses…

Rates of verbalizing by three children exhibiting moderate to severe language delays (delays of six months to two years) were increased through the systematic use of mands for verbalization, models for verbalization, and contingent positive consequences following utterances. Daily samples of each child's speech were collected during free play…