Unilateral adrenalectomy for benign causes of primary aldosteronism is an established procedure. The established surgical cure for aldosterone-producing adenoma justifies a thorough preoperative evaluation. No single test accurately identifies aldosterone-producing adenomas in patients with primary aldosteronism. However, a useful algorithm combines postural studies, computerized axial tomography, and adrenal vein catheterization for selective hormonal assay, if computerized axial tomography is negative or equivocal and the suspicion of aldosterone-producing adenoma is high. If an adrenal mass is present and biochemical studies suggest a diagnosis of aldosterone-producing adenoma, resection of the affected gland from a limited unilateral approach is indicated. Cure can be expected in 80 percent of cases. In the uncommon circumstance that the adrenal tumor was not an aldosterone-producing adenoma but a hyperplastic nodule, these patients may still be cured or more easily controlled with antihypertensive medications. Thirty-eight patients who underwent unilateral adrenalectomy are presented and discussed.