This book compiled by Professor Waifah Chen as a personal collection of his academic career path and accomplishments over the last 45 years with his colleagues and students at Lehigh University, Purdue University and the University of Hawaii covering the topics on Soil plasticity, Limit analysis, Plasticity in reinforced concrete, Theory of Beam-columns, Advanced analysis in steel and offshore structures, Steel design without the K-factor, and Safety analysis of concrete structures during construction. The book also includes some of Professor Chen's selected state-of-the-art papers, lectures and speeches delivered at some international conferences and symposiums as an invited keynote speaker.