Experiments have been undertaken into the generation and detection of ultrasonic transients in metals over a 40-MHz bandwidth, using pulsed-laser generation and interferometric detection. Longitudinal, shear, and surface waves have been investigated, and their form compared favorably to theory. The techique has been used to study the interaction of surface and bulk waves with slots in the surface of a plate. It has been shown that significant mode conversion occurred from surface to bulk waves and vice versa. The significance of this result to nondestructive testing is discussed.