This book contains the refereed proceedings of the International Conference on Modeling and Simulation in Engineering, Economics, and Management, MS 2012, held in New Rochelle, NY, USA, in May/June 2012.The event was co-organized by the AMSE Association and Iona College.The 27 full papers in this book were carefully reviewed and selected from 78 submissions. In addition to these papers a summary of the plenary presentation given by Ronald R. Yager is also included.The book mainly focuses on the field of intelligent systems and its application to economics and business administration. Some papers have a stronger orientation towards modeling and simulation in these fields.