Neuroendocrine tumors consist of a relatively heterogeneous group of carcinomas that are often well differentiated and associate with an indolent clinical course. ?While considered to be rare, their incidence has been on the rise. ?These tumors arise from neuroendocrine cells dispersed throughout the body and are generally incurable in the setting of metastatic disease. Due to their ability to produce hormones, their clinical presentations can be rather dramatic. ?Successful management requires an understanding of the disease process as a whole and a multi-modality approach with inputs from medical oncology, surgery, endocrinology, gastroenterology, pathology, radiology, and nuclear medicine. ?In this issue, leading investigators comprehensively review the carcinoid, islet cell carcinoma, adrenal cortical carcinoma, pheochromocytoma, medullary thyroid carcinoma, and Merkel cell carcinomas. ?Emphasis is on diagnosis, biology, and novel therapeutic strategies.