Over a 39-month period from 1 October 1983 until 1 January 1987, fine-needle aspiration biopsy (FNAB) was used in the routine screening of Saudi patients presenting at the King Fahad National Guard Hospital with mass lesions of the neck thought to be of thyroid origin. Eighteen malignancies were detected representing 19.4% of the 93 patients in the study and 41.9% of the 43 Saudi patients undergoing surgery. The true-positive rate of FNAB was 100% (three of three patients) with no false-positive FNABs. Of the 13 patients with an FNAB diagnosis termed "suspicious" who underwent surgery, 12 were found at surgery to have a malignancy. Surgery was also undertaken in three clinically suspicious patients despite initially negative FNAB results, and malignancy was found. No cases of malignancy were detected during follow-up of the FNAB-negative group not operated. The incidence of thyroid malignancy documented at surgery among Saudi patients in this study was approximately twice the rate previously reported for thyroid surgery from Saudi Arabia for patients evaluated by means not including FNAB. Thus, we conclude that FNAB provides a safe and useful tool to be used in addition to clinical evaluation and other available studies for the proper selection of Saudi patients with thyroid nodules who require surgery.