The book is dedicated to the issues of information operations recognition based on analysis of information space, particularly, web-resources, social networks, and blogs. In this context, open source intelligence technology (OSINT) solves the problem of initial analysis of modern-time information flows. The book provides a detailed description of mathematical principles of information operations recognition, based on mathematical statistics, nonlinear dynamics, complex networks theory, information and mathematical modeling, sociology. A separate chapter covers the applications of approaches from expert estimation theory and decision-making support to information operation recognition. The book is addressed to a broad circle of specialists from information technology and security domains.