This book presents the proceedings of the Ninth International Conference on Dependability and Complex Systems DepCoS-RELCOMEX, which took place in Brunów Palace, Poland, from 30th June to 4th July, 2014. The articles selected for this volume illustrate the variety of topics that must be included in system dependability analysis: tools, methodologies and standards for modelling, design and simulation of the systems, security and confidentiality in information processing, specific issues of heterogeneous, today often wireless, computer networks or management of transportation networks.