The technical aspects of microemboli detection are summarised in this paper. The physical principles of the microembolus signals detection, their ultrasound characteristics, the possibility of identification of microembolus signals in Doppler spectral wave and advised equipment settings have been reviewed. Then the methods of automatic microemboli detection are described, problems concerned with identification of the nature of the microembolic material and an advised time of monitoring patients with various indications. Technical progress in microembolus signals detection, especially improved methods of their automatic both detection and recording make a good prognosis for full explanation of the clinical relevance of this phenomenon.