The possibility to study a graphic recording (PCG) of auscultatory findings is often a helpful diagnostic tool for the clinician. Phonocardiography is a graphic recording of heart sounds and murmurs picked up by a microphone or sensor that is placed on the chest wall of the animal. The recorded sound may be filtered and printed on paper or displayed on the screen of a computer. Each filter amplifies sounds around a certain frequency (so called nominal frequencies) and dampens other sounds. The use of filters with different nominal frequencies of 50, 100, 200, 400 Hz and an aural filter (50-500 Hz) is useful to determine if a murmur has low, medium or high frequency components, and to remove disturbing background noise and respiratory sounds. To record ECG simultaneously with PCG is essential for timing the sounds and murmurs to the electrical activity of the heart. This timing may not be needed if S1 can be correctly identified. However, this is not always the case, especially not in cases with tachycardia or gallop rhythms. PCG has previously been recorded on multichannel ECG machines equipped with a PCG amplifier, but recording with a sensor based stethoscope* connected to a computer is now possible and for several reasons more practical for the future. A practical advantage with PCG is that it is instructive to have a graphic display of the heart sounds and murmurs at hand during discussion and explanation of diagnosis, and sometimes prognosis, with students and clients. For the practitioner PCG offers the opportunity to file heart sounds that may be useful for legal or insurance purposes. Evaluation of the timing, shape and frequency components of the heartbeat can be done objectively from the recording. For example, ejection murmurs may especially, at high heart rates, be very difficult to distinguish from holosystolic murmurs by auscultation but can easily be distinguished by phonocardiography. Time intervals on the PCG can also be measured, filed and compared with recordings from other animals or from consecutive examinations. A new interesting option, available with the Meditron PCG analysing system, is a possibility to perform two or three-dimensional spectral analyses of recorded murmurs. Future research will presumably develop this form of heart sound analysis, further improving the diagnostic possibilities of phonocardiography.