The current study attempted to capture in real time the unfolding of the relational operant using electroencephalography (EEG) and reaction time measures. Participants were exposed to relational pretraining to establish the contextual cues of Same and Opposite for two arbitrary stimuli. These cues were then used to establish a series of contextually controlled discriminations in order to create a simple relational network among a series of arbitrary stimuli. During the test for derived relations of Same and Opposite, EEG and reaction time measures were recorded for each individual test task during the acquisition of a stable derived relational response pattern. Participants were then exposed to an identical set of relational training and testing tasks with the important difference that an entirely different set of stimuli was used. EEG and reaction time measures were again recorded during the relational test phase. Results showed that reaction times decreased for all subjects across successive test tasks and from the first to the second stimulus set. EEG data also suggested that there was increasingly less higher cognitive activity during the derivation of successive stimulus relations within and across stimulus sets. Taken together these findings provide support for the idea that derived relational responding can be viewed as an operant activity that both develops and generalizes.