It is hypothesized that the backscatter of wave radiation from a rough boundary is the result of reflections from a large number of “facets” having random distributions of size and slope. This hypothesis developed into a mathematical model from which curves are computed for a number of values of mean size and rms slope. An explanation is offered for the lack of frequency dependence in reported backscatter measurements. The model is also fitted to some previously reported measurements of the backscatter of sound from the deep‐ocean bottom.