A patient who presented with bilateral frozen shoulders and unrecognized hyperthyroidism is described. Both frozen shoulder and the related shoulder-hand syndrome may occur in this setting. These poorly understood rheumatic conditions often are complications of stroke, spinal cord injury, or diabetes. Dysfunction of the autonomic nervous system is thought to be of pathogenic importance. It is postulated that the close resemblance of hyperthyroidism to activation of the sympathetic nervous system may underlie its association with frozen shoulder and shoulder-hand syndrome.