Measurements of turbulent kinetic energy k under surf zone waves are analyzed to show how k varies over depth, between breaker point and shoreline, and how k depends on the beach slope. It is found that the variation of k over depth is remarkably weak, large values being measured a few percent of the depth above the bottom. A simple model for the dissipation mechanism makes it possible to derive an empirical formula for the time-averaged k that accurately describes all the data considered reliable. ¿American Geophysical Union 1987