Morbidity after reoperation for persistent or recurrent primary hyperparathyroidism (pHPT) is higher than after primary surgery. According to our experience, there is a contrast between postoperative normalization of laboratory parameters and the quality of life/patient satisfaction after reoperation. Therefore the aim of the study was to analyze the outcomes of reoperations in comparison to primary surgery. We evaluated the patients' reported quality of life using the SF-36 (an accepted health status assessment tool) and complete prospectively documented perioperative and follow-up data including postoperative complications. Additionally, we searched for reasons why primary surgical intervention did not succeed. In a prospective cohort study the perioperative data of 653 consecutive patients with pHPT, including 75 reoperated patients (11.5%) who underwent parathyroidectomy between 1987 and 1999, were evaluated by uni- and multivariate analysis. At a median 78 months (6-156 months) postoperatively, all patients underwent a planned follow-up that included the SF-36, physical examination, and laboratory investigations. A total of 51 reoperated patients were available for follow-up. Postoperative alleviation of symptoms or being symptom-free was reported by 70.6%. Patients after reoperation had lower SF-36 scores in all health domains postoperatively than patients after a primary operation. Of the reoperated patients, 19.6% stated that after evaluating the development of their complaints they would not consent to reoperation again. Subgroup analysis showed that 80% of patients with postoperatively persistent pHPT, 60% of those who did not observe symptom alleviation, and 44% of those after sternotomy were in the group of dissatisfied patients. Surprisingly, none of the patients with more than one reoperation, only two of the five patients with permanent recurrent laryngeal nerve injury, and only one of the four patients with persistent hypoparathyroidism were dissatisfied overall. Parathyroidectomy resulted in normocalcemia in 90.2% of the reoperated patients, with an operative morbidity of 27.4% and no mortality. After an unsuccessful operation for pHPT, patients should be treated at an expert center to avoid persistent hypercalcemia. Reoperations necessitating sternotomy should be restricted to patients with severe symptoms and signs.