These proceedings were held during the ASM International Materials Solutions Conference and Exposition in Cincinnati, OH on November 1-4, 1999. The purpose of this symposium was to provide a forum for technical exchange on the latest research and developments in steel technology, as well as future technical challenges. Most of the papers that were presented appear in these proceedings. The papers are either focused on microalloyed and thermomechanically-controlled processed steel products or conventionally rolled and heat treated steel products with balanced properties for use in many structural applications. The steels, designed for such applications as bridges, construction vehicles, linepipe, shipbuilding, and mining equipment, exhibit high strength and toughness and superior weldability to provide designers and fabricators with new opportunities to design and fabricate cost-effective structures with longer fatigue life. Contents include: Twenty seven papers included on the following topics: Plenary session Heat-treated and copper-alloyed plates Thermomechanically control-processed plates Other plates and structural shapes Weldability issues.