The interaction of acoustic energy with a free liquid surface provides a means for rapid formation and readout of an acoustical hologram. Although a two-step holographic process is possible, involving recording the liquid-surface hologram on a photographic transparency, the real-time imaging capabilities are of most interest and provide the basis for all of the current use of equipment in industrial testing and biological imaging. The use of acoustic lenses to focus the object field of interest into the hologram is particularly useful for achieving good resolution. Industrial test applications and imaging of biological systems in real time are best illustrated using video tapes or motion pictures.