This article reviews agreement, disagreement and need for future research of the thyroid nodule guidelines published by the British Thyroid Association, National Cancer Institute, American Thyroid Association and the joint, transatlantic effort of three large societies, the American Society of Clinical Endocrinologists, Associazione Medici Endocrinologi and the European Thyroid Association, published in 2010. Consensus exists for most topics in the various guidelines. A few areas of disagreement, such as the use of scintigraphy, are mostly due to differences in disease prevalence in different countries. Most of the discordance, for example, on the use of calcitonin screening or fine-needle aspiration cytology classification, could probably be resolved by further expert discussions, as the basis is the same published evidence. Importantly, owing to a current lack of evidence in many areas, clinically very relevant areas of uncertainty need to be addressed by further research. This situation applies, for instance, to better definition of ultrasound malignancy criteria and the evaluation of emerging new diagnostic and therapeutic techniques, including molecular markers. For clinicians who advise individual patients, these areas of uncertainty can currently only be resolved by sound management on the basis of clinical judgment, experience and patient preference.