This article reviews the current understanding of how dopamine agonists stimulate growth hormone secretion in normal individuals, yet suppress growth hormone secretion in acromegaly patients. Although bromocriptine normalizes growth hormone or somatomedin C hypersecretion in a minority of patients, a significant number of subjects have a clinical response. Side effects of bromocriptine treatment and newer dopamine agonists are discussed. These drugs can be useful medical therapy, either used alone in selected patients or in combination with other therapeutic modalities.