Abstract Behavior and its associated executive processes can be categorized into lower-level movements, but also into higher-level states. States are controlled on a moment-to-moment basis by goals and likely implemented by specific brain circuits, including dorsal prefrontal cortical structures. The ability to properly select behaviors and to switch between them is critical for healthy cognitive functioning. Disruption of state control is a hallmark of addiction. Understanding how the brain implements and switches between states therefore offers the hope of improve their control. The central premise of this proposal is that understanding the neural control of states in macaques can help us understand neural control of states more generally. We believe this is best done in freely moving animals because behavioral expression is too constrained to be interpretable in typical laboratory contexts. A major barrier is the difficulty in tracking macaques’ body positions, which is essential for state identification. We have recently solved the tracking problem. Using an electrophysiological recording system amenable to recording in a freely moving environment, we will record responses of hundreds of neurons in dorsal anterior cingulate cortex (dACC) and the dorsolateral prefrontal cortex (dlPFC). These cortical regions, which are unique (dlPFC) or greatly modified (dACC) in the primate order, are strongly associated with control of behavior, are associated with simple cognitive states and with regulation of behavior in humans, and are prominently dysregulated in addiction. They also have strong and direct projections to the primary and secondary motor systems, putting them in an ideal position to drive behavior, and suggesting they may have a high-level relationship with control of behavior. However, while they are linked to these processes, we know almost nothing about their neuron-level relationship with control of behavior. We will place animals in our large cage system and have them perform a foraging task in which they naturally cycle through behaviors and then link them with brain activity in dACC and dlPFC. This will let us resolve several outstanding issues, including what role these regions have in behavioral control and how they relate to each other.