Germanium is a material with optimal infrared (IR) transmission properties but poor mechanical properties[1]. As a result, repeated water drop impacts on polished Ge windows with velocities greater than 170 m/s produce considerable amounts of surface and subsurface damage (see Figure 1). This results in IR transmission loss through these windows[2]. The mechanics of the water drop/solid surface interaction has been amply described in the literature[3] and will not be discussed here. In order to maintain optimum IR system performance, one needs to monitor the damage evolution on these windows. The technique required should be fast, quantitative, non-contacting and easy to interpret. In this paper we examine the use of light scatterometry as a possible approach for monitoring damage evolution.