The goal of the Advanced Research Workshop is to bring together scientists and practitioners interested in recent developments in exploiting data and text mining techniques for countering terrorist activities on the Web. The emphasis will be placed on presenting available methods and tools that can alleviate the information overload of intelligence and security experts.  The main areas to be discussed include terrorism origins, the threats of the "Dark Web", web content mining and Open Source Intelligence (OSI), text mining and data mining methods for security applications, and methods of Financial Intelligence (FI) for stopping terror financing activities.   State-of-the-art solutions and open problems in the defense against web-based terrorism will be highlighted by world-renowned experts in intelligence and security informatics (ISI) from NATO, Partner, and Mediterranean Dialogue countries.