The purpose of this study was to measure and compare the In- vitro shear bond strengths of two commercial dental adhesive systems. All Bond 2 and Prime & Bond 2.0 to dry, moist and overwet dentine. Data generated from this In-vitro study indicated that mean bond strengths of All Bond 2 and Prime & Bond 2.0 were better to moist dentine than to dry dentine. The mean bond strengths to dry dentine were better than over wet dentine surfaces while the moist dentine surfaces exhibited significant stronger bond strengths as when compared to over wet dentine surfaces for both the adhesive bonds