The task of extending Skinner's (1957) interpretation of verbal behavior includes accounting for the moment-to-moment changes in stimulus control as one speaks. A consideration of the behavior of the reader reminds us of the continuous evocative effect of verbal stimuli on readers, listeners, and speakers. Collateral discriminative responses to verbal stimuli, beyond mere echoic or textual behavior, are potential sources of control and must be included in any complete account of both verbal and nonverbal behavior.