Parathyroid carcinoma constitutes a rare cause of hyperparathyroidism. Five patients, presenting with symptoms and clinical signs of parathyroid hyperfunction, were diagnosed with parathyroid carcinoma in our department over a 12-year period. The experience we gained in the management of these tumors is presented. The aim of this study is to elucidate the clinical features of the disease, the surgical treatment, and the sensitivity of the imaging modalities used to enhance the diagnostic ability. Preoperative recognition and intraoperative identification of this rare endocrine malignancy require a high index of clinical suspicion. Intraoperative awareness is needed of the malignant potential of the encountered lesion.