Objective: The authors determined the usefulness of frozen section (FS) evaluation in the operative management of follicular lesions of the thyroid. Summary Background Data: Fine-needle aspiration (FNA) cannot reliably discriminate between benign and malignant follicular lesions of the thyroid. Accordingly, FS evaluation is used routinely to guide intraoperative management. Methods: One hundred twenty-five consecutive patients with follicular thyroid lesions who underwent surgical exploration at the Johns Hopkins Hospital were reviewed. Results: Frozen sections were categorized in 104 of 120 patients (87%) as 'follicular lesion, defer to permanent section,' rendering no useful clinical information. In only 4 of 120 patients (3.3%) did FS evaluation correctly modify the operative procedure. Notably, in six cases (5.0%), an incorrect FS evaluation misled the surgeon, resulting in four misguided operations. Conclusion: Frozen section evaluation is of minimal diagnostic value for follicular thyroid lesions, rendering no additional information 87% of the time; it prolongs the operation, increases costs, and leads to misguided interventions. Until a more definitive diagnostic tool exists for follicular thyroid lesions, FS evaluation could be omitted, resection of the lobe with the nodule could be performed, and the definitive operative management could be based on the final permanent histology.