Inhibitory control plays an indispensable role in cognitive flexibility. Nevertheless, the neurophysiological principles underlying this are incompletely understood. This owes to the fact that the representational dynamics, as coded in oscillatory neural activity of different frequency bands has not been considered until now—despite being of conceptual relevance. Moreover, it is unclear in how far distinct functional neuroanatomical regions are concomitantly involved in the processing of representational dynamics. We examine these questions using a combination of EEG methods. We show that theta-band activity plays an essential role for inhibitory control processes during cognitive f lexibility across informational aspects coded in distinct fractions of the neurophysiological signal. It is shown that posterior parietal structures and the inferior parietal cortex seem to be the most important cortical region for inhibitory control processes during cognitive f lexibility. Theta-band activity plays an essential role in processes of retrieving the previously inhibited representations related to the current task during cognitive f lexibility. The representational content relevant for inhibitory processes during cognitive f lexibility is coded in the theta frequency band. We outline how the observed neural mechanisms inform recent overarching cognitive frameworks on how f lexible action control is accomplished.