Microembolic signals (MES) are a frequent finding in varying sources of cerebral embolism. Spontaneous MES might be derived from embolic sources within the heart or from mostly atherosclerotic vessel wall changes of the brain-supplying arteries. MES have been observed under a variety of circumstances, especially in symptomatic carotid stenosis, high-risk cardiac conditions, and surgical procedures. MES analysis is a promising field of research, giving insight into important aspects of stroke pathophysiology. Potential indications for MES detection could be the analysis of treatment effectiveness, as well as the monitoring of surgical intervention of the brain-supplying arteries.