The effects on the strength, hardness, and ductility of a series of well-annealed palladium-silver alloys due to hydrogen exposure were investigated at various temperatures. The results indicate that the temperature at which hydrogen exposure occurs can have a significant effect on the degree to which these mechanical properties are altered. At relatively low temperatures, it was found that the strength and hardness of the alloy are increased, while ductility is decreased upon hydrogen exposure. In alloys where such changes are observed, the magnitude of these changes was found to diminish as the silver content increases. Above a certain hydrogen exposure temperature-the value of which decreases with increasing silver content-the strength, hardness, and ductility of the alloy show no significant changes as a result of hydrogen exposure. (C) 2014 American Society of Civil Engineers.