Modern intelligence, which emerged in its present form after the Second World War, has undergone numerous changes over the last seven decades. One of the main factors in the transformation of intelligence at the end of the 20th and the beginning of the 21st century is certainly the advent of information and communication technologies (ICT), while the segment in which this transformation was the most dramatic is intelligence based on open sources (OSINT). This transformation is not a new phenomenon at the global level. The development and availability of personal computers and the Internet, and their connection with telecommunication technologies have influenced almost all aspects of modern life, especially the work process, and in that sense, it is almost impossible to imagine, but also to find a profession that does not depend on personal computers, the Internet, and various mobile devices that have become both a means of work and an object of work in the process of work. Information and communication technologies (ICT) have also become an integral part of all known sectors of the economy, both manufacturing and nonmanufacturing; they are present in education, culture, science, transport, banking, tourism; in both the public and private sector. In short - ICTs are ubiquitous today. Modern intelligence services have therefore had the task of following global trends driven by the rapid development of Internet technologies and the increasing use of modern communication technologies, especially 'smart' devices. Authors summarized some basic terms and notions in Intelligence Studies - intelligence, intelligence process, intelligence disciplines, and collection of data as part of intelligence process. Then they provided a brief historical overview of the impact of open sources on the development of intelligence, with special focus on the end of the 20th and the beginning of the 21st century, with an emphasis on the impact of new ICTs on this aspect of intelligence. At the end, an effort was made to produce an overview of some of the most significant theoretical reviews of this process from the perspective of the discipline of Intelligence Studies. Authors conclude that OSINT is not just a matter of monitoring the media of other countries or collecting data through diplomatic missions. The amount of daily information in terms of news produced on the Internet every minute, including social networks, has reached a level where it is pointless to 'manually' cover news from around the world, as there is a highly developed and sophisticated software that automates collection and allows for selection of information relevant to the person organizing the collection. In this respect, the amount of software OSINT tools available to an individual today by far exceeds the capacities possessed by the great power intelligence systems during the Cold War.