The trend toward limited exploration for primary hyperparathyroidism (1 degrees HPT) has stemmed from advances in sestamibi scanning, gamma probe technology, and intraoperative parathyroid hormone monitoring (iPTH). Prior to widespread application, directed parathyroidectomy must be shown to meet the high standards of conventional cervical exploration. In this prospective, nonrandomized trial, results of parathyroidectomy utilizing the gamma probe, iPTH, or neither technique were evaluated. Altogether, 150 patients underwent parathyroidectomy utilizing the gamma probe (n = 50), iPTH (n = 50), or neither technique (n = 50). Each group was evaluated for operating time, length of hospitalization, cure rate, morbidity, mortality, and cost. A telephone survey was conducted with 25 patients in each group (n = 75) to address patient satisfaction. The gamma probe localized the abnormal gland in 66% of patients and confirmed cure intraoperatively in 84%. In the iPTH group, a more than 50% decrease from baseline occurred in 98%. The mean operating times were 76, 84, and 90 minutes, respectively (p = 0.16); and the mean length of hospitalization was 1 day. The biochemical cure rates were 98%, 100%, and 96%, respectively (p = 0.17). Total costs were $4476, $3918, and $3905, respectively. A total of 96% of patients in all three groups were "very satisfied" with their surgical procedure. Directed parathyroidectomy utilizing the gamma probe or iPTH assay does not significantly alter the operating time, length of hospitalization, cure rate, morbidity, mortality, or patient satisfaction when compared to conventional exploration in our practice. The probe is more expensive and was not a consistently reliable tool for localizing parathyroid pathology. PTH monitoring reliably predicts cure intraoperatively.