The clinical usefulness of electric source imaging (ESI) in presurgical epilepsy evaluation has now been demonstrated; however, its use in clinical routine remains somewhat limited. Here, we discuss the added clinical value of ESI and how its integration in the presurgical work-up of epilepsy patients can be optimized. We present methodological differences of ESI on interictal and ictal epileptic activity as well as their evaluation compared with intracranial EEG data. Beyond the choice of patterns used for ESI, the choice of inverse methods can have tremendous impact on source imaging results. It is of great clinical interest that during recent years several inverse methods have been developed that are sensitive to the spatial extent of the generators of epileptic activity. In this regard, we discuss the performance of different approaches. Advanced inverse methods that consider the temporal evolution of the EEG signal even allow for localizing deep generators with good spatial accuracy. In summary, recent methodological advances in ESI foster its application in clinical practice.