Neuromodulation is an important and frequent therapy applied, among others, in the management of chronic pain. Neuromodulation is defined as ¿a therapeutic alteration of activity in the central, peripheral or autonomic nervous systems, electrically or pharmacologically, by means of implanted devices¿. It encompasses a focal, minimal invasive and reversible approach. Due to its invasive character with some more risks than other modalities of pain treatment, neuromodulation is generally applied as the last option when all other therapies have failed. The overall success rate of this treatment modality is about 50%. It is often the only modality that may help a particular patient. However, there are still many chronic pain patients in whom neuromodulation was attempted with suboptimal or even less than satisfactory results. For the sake of this pool of patients it is an imperative to understand the effects occurring during a neuromodulation therapy and to design stimulation in such a way that a larger number of patients can be treated, while giving them an improved satisfaction with the therapy.