Electromagnetic leakage or cross talk between transmitter and receiver represents a severe limitation on the usefulness of continuous‐wave (CW) ultrasonic methods at high frequencies. The problem of leakage is, however, entirely eliminated by use of a scheme known as the sampled‐CW technique. The role of the sampled‐CW technique in eliminating leakage is explicitly demonstrated by contrasting the results of CW and sampled‐CW measurements under a variety of conditions.