Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are relatively rare and complex neoplasms that present many clinical challenges. Most GEP-NETs are sporadic, but they can be multiple and a component of a familial syndrome. Assessment of the location and extent of GEP-NETs is crucial for management and a number of novel imaging modalities are under evaluation with the principal goal of increasing sensitivity for the detection of micro-metastases while retaining specificity. The appropriate diagnosis and treatment of neuroendocrine tumors often involves collaboration between specialists in multiple disciplines, using specific biochemical, radiologic, and surgical methods. Management strategies include surgery, radiological intervention, cytotoxic chemotherapies, somatostatin analogs and novel biological agents such as sunitinib and everolimus. Other biological agents, new chemoteraphy regimens and somatostatin-tagged radionuclide therapies are also under investigation. In spite of this, comparison between therapeutic modalities is currently difficult. Further studies are warranted to individualize and optimize the diagnosis and treatment of these tumors.