Studies of the effect of chemical bonding on the measured joint strength of bonds formed between polymers and rigid substrates have been carried out. Various treatments have been applied to glass surfaces before bonding to polymeric overlayers. These treatments have included reaction of glass with mono- and trialkoxysilanes, urethanes, silanated polybutadienes, and polysiloxane layers. Effects on the resulting joint strength varied from an insignificant level to a thirtyfold increase. Comparisons of various results of joints between glass and a polybutadiene overlayer, summarized in this report, suggest that a transition layer such as a polysiloxane layer must be introduced before positive effects of chemical bonding are obtained. When this transition layer is present, the measured strength of the joint is found to increase as the number of chemical bonds increases. In experiments involving the bonding together of two identical polybutadiene layers, the joint strength was found to increase in direct proportion to the number of assumed interfacial chemical bonds. (Author).