This report summarizes the Washington State Department of Transportation's (WSDOT's) 10 years of experience with "epoxy" and "methyl methacrylate" (MMA) thin polymer bridge deck overlays. WSDOT uses a modified concrete as its primary type of bridge deck overlay, but in some cases a bridge's physical characteristics, such as lightweight design or narrow roadway width, will not allow using a modified concrete overlay. Thin polymer overlays provide an alternative. Thin polymer overlays offer more rapid construction, curing in 4 to 8 hours compared to 42 hours for a modified concrete overlay. Thin polymer overlays are lightweight (due to their 3/8 in. thickness, approximately 5 lb/SF versus 19 lb/SF for a modified concrete overlay) and are generally less labor intensive and require less specialized equipment than a modified concrete overlay.