The 13th IFAC Symposium on Large Scale Complex Systems: Theory and Applications (IFAC LSS 2013) is sponsored by IFAC TC5.4 - Large Scale Complex Systems, co-sponsored by some other IFAC TCs, IFORS, IMACS, IFIP, IEEE Shanghai Section, and Chinese Association of Automation (CAA). The Symposium is to discuss new developments in methodologies and techniques useful in handling complexity in analysis, modelling, control and optimization of large scale complex systems. The methodologies and tools for the complexity analysis are to be among the key issues of the Symposium. A number of application areas will be addressed. Special attention will be paid to large scale complex systems which are closely connected with the human daily’s life, such as urban traffic systems, water systems, environmental systems, power supply systems, etc. The IFAC LSS 2013, organized by Shanghai Jiao Tong University (SJTU), East China University of Science and Technology (ECUST), Key Laboratory of System Control and Information Processing, Ministry of Education (SCIP), and Shanghai Association of Automation (SAA), will be held in Shanghai, a modern metropolis with traditional oriental and local culture.