Thyroid and parathyroid are easily accessible and common sites of palpable nodules; in this era of ultrasound, nodules in these tissues are being detected at an increasing rate and it is now estimated that up to 70% of the population in North America has an ultrasound-detectable thyroid nodule. The procedure of choice to triage patients for surgery or surveillance is the needle biopsy. Since thyroid cancer is one of the few malignancies that is showing an increase in incidence, it is imperative that Pathologists know the approach to the interpretation of biopsies.Moreover, the correct diagnosis of these lesions will lead to more appropriate surgical intervention and prevent repeat surgeries. At the mement, many patients undergo emithyroidectomy based on inconclusive pre-operative evaluation, and after definitive diagnosis of cancer on surgical pathology of the thyroid lobe, a second surgical procedure is required.This volume in the series would be designed to address that specific issue in detail and enhance the rational management of patients with neck nodules. The text will have two parts, the first dealing with the more common thyroid biopsies, and a complementary second part on parathyroid biopsies that are either frequent surgical specimens or uncommon aspirates that may be mistaken for thyroid.