Drug-resistant obsessive-compulsive disorder and aggressive behavior are two severely disabling psychiatric conditions which may carry a certain burden on the patients themselves and on their families. In the last decade, the fields of interests of deep brain stimulation (DBS) also encompass psychiatric disorders, supported by imaging and neurophysiological techniques. We here report our institutional experience with the two above-mentioned disorders, describing the procedure commonly employed and the results obtained. Refinement of such techniques, possibly relying on advanced magnetic resonance imaging (MRI), together with probabilistic pictures of field of activation models, could shed more light into this complex field of investigation; further studies are necessary to confirm and make actual results a starting point to new and more precise methodologies in this stimulating research field.