Abstract: An adhesive system that can be used for bonding together fiberglass reinforced polyester (FRP) panels is provided. The adhesive system is comprised of a "hardener component" containing a polyester or polyether triol, paraphenylene diamine or ortho-phenylene diamine, and desirably a tin compound catalyst, and a "base component" containing an aromatic diisocyanate. The two components are mixed together just prior to bonding and the mixture is spread on the FRP panel surfaces desired to be bonded together. The panels are assembled and held clamped together until the adhesive sets.