The thyroid gland was investigated in 43 persons (12 healthy volunteers, 31 patients with diseases of the thyroid gland) with a new colour Doppler system (angiodynography). In euthyroid persons (normal thyroid gland, diffuse or multinodular goitre) only a few vessels were detected. In cases with Graves' disease however, hypervascularization was evident. Autonomous adenomas had a hypervascular periphery, whereas our two carcinomas showed a high vascularisation in the nodule. Angiodynography might become an important diagnostic tool for the evaluation of thyroid glands. The number of radionuclide studies and punctures might be limited.