The neuroendocrine tumors (NET) of the gastro-entero-pancreatic area (GEP) represent a heterogeneous group of malignancies from the histologic, clinico-laboratoristic (functioning and non-functioning variants), and therapeutic point of view. It is an issue becoming more frequent for the diagnostic imager, being radiologist as well as nuclear physician. Imaging (together with biopsy) plays a key role in the diagnostic assessment and staging (including grading and prognostic definition), in evaluating response to treatment, and in follow-up of GEP-NET. Multislice computed tomography (MSCT), octreoscan and PET-CT are the most widely diffuse and accurate imaging modalities employed in this setting. Other methods, such as Magnetic Resonance and Endoscopic Ultrasound, may also play a significant role.