Thyroid fine needle aspiration biopsy has become an important tool in the diagnostic armamentarium of the endocrinologist. It is the safest, most cost-effective means for detecting thyroid cancer. Surgical intervention rates can be lowered by almost 50% by using fine-needle aspiration to identify nodules most likely to be malignant. In addition, the incidence of cancer in excised nodules can approach 50% when surgery is planned with the help of fine needle aspiration biopsy. This short review will examine the utility of fine needle aspiration biopsy in the differential diagnosis of the thyroid nodule, examine its accuracy with the most common neoplasms, and assess its role in the contemporary evaluation of the thyroid gland.