M-mode echocardiography is considered to be obsolete by many. The technique rarely is included in American Society of Echocardiography standards documents, except for M-mode measurements, which have limited value. The superior temporal resolution of M-mode echocardiography is frequently overlooked. Doppler recordings reflect blood velocity, whereas M-mode motion of cardiac structures reflect volumetric blood flow. The 2 examinations are hemodynamically complementary. In the current digital era, recording multiple cardiac cycles of two-dimensional echocardiographic images is no longer necessary. However, there are times when intermittent or respiratory changes occur. The M-mode technique is an effective and efficient way to record the necessary multiple cardiac cycles. In certain situations, M-mode recordings of the valves and interventricular septum can be particularly helpful in making a more accurate and complete echocardiographic cardiac assessment, thus helping to make the examination more cost-effective.