During behavior, cortical neurons are continuously integrating task-relevant information from the opposite hemisphere. While the importance of bilateral integration to behavior may appear obvious, its underlying neural mechanisms are almost entirely unknown. Naïve models of processing often assume that bilateral integration only occurs at higher cortical levels, despite an abundance of interhemispheric (IH) circuits in the primary sensory cortices. However, the basic circuit logic by which the corpus callosum operates remains poorly understood. To reveal the logic of bilateral integration and to dissect the role of its diverse circuitry, we are combining a novel bilateral discrimination behavior with cell-type specific optogenetic silencing, bilateral electrophysiology, and statistical modeling. Initially, mice are trained to discriminate between homotopic (HM, matching) and heterotopic (HT, non-matching) bilateral cues. While mice perform the task, we record high-density electrophysiological activity across both primary somatosensory cortices (S1). We discovered that goal-directed processing flexibly controls the flow of tactile information to favor the reward conditioned bilateral cues. Contrary to expectations, we found interhemispheric facilitation to be the primary driver of the goal-directed bilateral percept. In naïve (untrained) mice, S1 neurons were primarily suppressed by ipsilateral input, revealing a default suppressive mode of bilateral integration that is distinct from the goal-directed percepts. Greater synchrony between neurons in opposite hemispheres appears to be a primary mechanism for enhancing goal-directed stimuli. We hypothesize that bilateral synchrony preferentially activates downstream areas involved in action selection. Using latent variables derived from a population of S1 neurons, we show that the goal-directed representation of bilateral space is strongly modulated by behavioral performance. Ultimately, we reveal the contextual flexibility of IH circuits and the spatially-specific transfer of information between hemispheres.