Primary adrenal tumors were removed in 24 patients by the posterior retroperitoneoscopic approach, maintaining tumor-free parts of the ipsilateral adrenal gland. These partial adrenal resections did not cause a significantly different operating time or blood loss compared to 58 complete adrenalectomies performed during the same period. All 20 patients with hormonally active tumors are biochemically and clinically cured (mean follow-up 18 months). In selected cases the retroperitoneoscopic subtotal adrenal gland resection is a safe procedure, which can potentially maintain the function of the adrenal gland's cortex.