Deep brain stimulation (DBS) has become a well-accepted medical therapy in the treatment of movement disorders such as Parkinson's disease, and is currently under investigation as a treatment for other disorders, including epilepsy. Although DBS is widely used, its therapeutic mechanisms remain poorly understood. Recent research shows that seizures are network-level phenomena, but the incomplete knowledge of neural circuit function has left a gap in our understanding of how disruption at a molecular or cellular level generates epilepsy. In addition, DBS may potentially provide the opportunity to selectively modulate targeted brain regions and related networks. Therefore, a better understanding of the relationship between normal neural networks and epileptogenic networks, as well as the role of DBS in the modulation of neural networks will help us to find the optimal stimulation targets and parameters to achieve a better therapeutic effect. This review will outline the most recent advances in the relationship between normal brain networks and epileptogenic networks, and the modulation of DBS on the excitability of epileptogenic networks. We will then discuss how to optimize DBS stimulation targets and parameters by taking into consideration the concept of network modulation in order to improve treatment of epilepsy in the future. (C) 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.