Experiments were conducted to assess the time-dependent behavior of brittle rock and of rough, unfilled tension joints as a function of stress state and water content at ambient temperature. Quasi-static tests were performed on Westerly granite, Nugget sandstone and Tennessee marble at confining pressures up to 10,000 psi. Creep was measured on granite and sandstone at 1,000 psi, 5, 000 psi and 10,000 psi confining pressure. Finally, creep tests were carried out on granite in uniaxial tension. Both axial and lateral strains were measured in all experiments.