The authors present an analysis of clinical, angiographic and operation finginds in 11 patients showing large chemodectomas with involvement of the common, external and internal carotid arteries and jugular vein. The carotid body angiography was found to be of great diagnostic value. In the presence of a patent internal carotid in 10 cases radical chemodectomy was performed, preserving the patent internal carotid and the vein. In case of a pathologically convoluted internal carotid the common carotid artery was resected with an end-to-end anastomosis. Late results were favourable even in patients with histological signs of an incipient malignant transformation of chemodectomy.