This two-volume set constitutes selected papers presented during the Second International Conference on Science, Engineering Management and Information Technology, SEMIT 2023, held in Ankara, Turkey, during September 14-15, 2023. The 44 full papers and 2 short papers presented were carefully reviewed and selected from 409 submissions. The papers cover the following topics:  Part I - Decision Analysis and Expert Systems; Machine Learning, Data Analysis and Computer Vision in Healthcare and Medicine; Smart Production, Transportation and Supply Chain Systems; Information Technology and Data Science in Industry. Part II - IoT, Blockchain, and Cyber Security in Complex Systems; Real-Time Data Analysis and Simulation in Engineering Systems; Digitalization and Artificial Intelligence in Manufacturing/ Service Industries; Soft Computing and Artificial Intelligence in Engineering Management and Marketing.