INTRODUCTION: Scintigraphic evaluation of the thyroid gland enables determination of the iodine-123 iodide or the Tc-pertechnetate uptake and distribution and remains the most accurate method for the diagnosis and quantification of thyroid autonomy and the detection of ectopic thyroid tissue. In addition, thyroid scintigraphy and radioiodine uptake test are useful to discriminate hyperthyroidism from destructive thyrotoxicosis and iodine-induced hyperthyroidism, respectively.METHODS: Several radiopharmaceuticals are available to help in differentiating benign from malignant cytologically indeterminate thyroid nodules and for supporting clinical decision-making. This joint practice guideline/procedure standard from the European Association of Nuclear Medicine (EANM) and the Society of Nuclear Medicine and Molecular Imaging (SNMMI) provides recommendations based on the available evidence in the literature.CONCLUSION: The purpose of this practice guideline/procedure standard is to assist imaging specialists and clinicians in recommending, performing, and interpreting the results of thyroid scintigraphy (including positron emission tomography) with various radiopharmaceuticals and radioiodine uptake test in patients with different thyroid diseases.