The International Workshop on Chaos-Fractals Theories and Applications 2012 (IWCFTA 2012) was held successfully in Dalian, China, from October 18-21, 2012. This year’s workshop attracted over 100 participants from different parts of the world who came to Dalian to present their latest research findings and results in areas related to chaos, fractals, bifurcations, complex systems, and including all aspects of the general nonlinear systems research. A number of outstanding researchers in the field were invited to present keynote lectures during the workshop, including Prof. A Leonov and Dr N.V. Kuznetsov from St. Petersburg State University; Russia, Prof. Ivan Zelinka from Technical University of Ostrava, Czech Republic; Prof. Michael Small from University of Western Australia, Australia; Prof. Zengqiang Chen from Nankai University, China; and Prof. Gongfy Liao from Jilin University, China. A range of topics were presented, including hidden attractors, evolutionary dynamics, roulette game, encryption technology using hyperchaos, and chaos in discrete systems. The technical program of this year’s workshop was exceptionally broad covering traditional nonlinear systems and extending to complex networks and systems. This broad coverage reflects on the diverse theoretical interests and wide variety of possible applications of nonlinear systems, and clearly indicates the continual momentum of researchers working in this field.