The subthalamic nucleus (STN) is a critical structure underlying self-control. It is implicated in inhibitory processes and its position within the indirect pathway and receiving hyperdirect cortical projections emphasizes its role as a nexus for integration. Clinically, the STN is a target for deep brain stimulation for Parkinson’s disease and obsessive-compulsive disorder (OCD) with preclinical evidence suggesting a role for addictions. Here I will describe a body of research in OCD patients with deep brain stimulation targeting the associative-limbic STN focusing on subtypes of decisional impulsivity. I argue that these disparate findings can be linked through the effect of STN stimulation on decreasing decision thresholds, and on valence and affect. I further elaborate on a novel transcranial magnetic stimulation application using paired associative stimulation demonstrating the capacity to modulate response inhibition via cortical-STN pathways. Together, these findings expand on STN function and self-control and highlight its translational and therapeutic relevance to psychiatric disorders.