The major progress in fiberglass-reinforced polyester composites since the 1940s has been attributed to the development of silane coupling agents that improve the bond across the interface [1]. Among the best coupling agents for polyesters is 3-methacryloxypropyltrimethoxysilane (γ-MPS), first described in 1962 (Fig. 1). Other methacrylate-functional silane coupling agents show comparable coupling activity in fiberglass reinforced general purpose polyester composites [2] (Table 1). The bond between glass and polyester with these coupling agents was “perfect,” i.e., fracture surfaces after 2-h water boil showed essentially no interfacial bond failure.