At least 8 separate dominant syndromes have been described which have hyperfunctioning endocrine tumors as an important component. Scattered reports in the literature suggest that there may be an additional syndrome, in which extra-adrenal paragangliomas (often multiple), pituitary adenomas, and parathyroid hyperplasia coexist. Of 3 such cases described to date, 2 have included information about the family history, which in each case suggested dominant inheritance. This would presumably be a less common syndrome than the others recognized previously, so that full evaluation of endocrine findings and family history in future cases will be important for developing our understanding of the syndrome.