The study presented in this report evaluated the potential durability gained by the use of penetrating sealants on concrete bridge decks. The primary conclusion of this report is penetrating sealants are an effective means of protecting concrete bridge decks. The factors affecting the depth of penetration are identified through a fundamental approach and the literature on penetrating sealants, concrete deterioration, concrete durability, and concrete permeability. Properties and the use of silane, siloxane, and high molecular weight methacrylate sealers are discussed. The use of high molecular weight methacrylate is recommended based on its extensive applications in the field. Silane and siloxane penetrating sealers can be used on new decks. High molecular weight methacrylate (HMWM) in conjunction with silane sealers can be used on cracked decks. If the maximum crack width is between 0.002- and 0.08-inches, silane and HMWM sealers can be applied provided adequate drying period is maintained between silane and HMWM applications. A field test method for evaluating the effectiveness of penetrating sealants is outlined. Electrical resistivity measurement technique is proposed as a means of obtaining field data. Cores are taken from the samples cast, cured, treated, and subjected to the same environmental conditions as the concrete bridge deck. These cores can be used for recording visible and effective depth of penetrations using splitting test and the abrasion test method recommended by Alberta Transportation and Utilities, respectively.