The response of alloy steels to dynamic strain aging (straining (about 2%) at relatively low temperatures) in both the quenched and tempered and ausformed conditions was investigated. Strength, ductility, and toughness were measured as a function of straining and tempering temperatures. Structural observations were made on the strained and unstrained steels. By appropriate choice of strain and tempering temperatures, the strength of both the quenched and tempered and the ausform steels was increased by about 40,000 psi. In the ausform steels, yield strengths of 270, 000 psi were achieved by dynamic strain aging with a reliability ratio (Kc/oys) of one. Since the slope of Kc/oys vs. oys is small, it is suggested that this process may be used to attain yield strengths of 300,000 psi is steels with exceptional toughness.