The traditional exam system is in crisis as it focuses on rote memorization and high loads, which increase student anxiety and reduce the level of practical training. In response to these challenges, more attention is being paid to innovative assessment formats, such as open-book exams (OBE), aimed at developing critical thinking, self-regulated learning, and deep understanding of the material. Methodology and Methods. A systematic review analyzed 20 studies published between 1950 and 2025, involving 3,349 participants from 11 countries. The studies were conducted in accordance with PRISMA guidelines. Databases such as PubMed, Web of Science, and Scopus were used, along with citation and reference analysis to identify relevant publications. Data were collected and synthesized thematically to identify key trends and effects of OBE implementation. Results. The review showed that OBEs significantly reduce student anxiety by focusing on understanding and applying knowledge rather than mere memorization. They promote critical thinking, self-learning skills, and deeper engagement with learning materials. However, the effectiveness of OBEs depends on proper question design, preparation strategies, and implementation. Scientific Novelty. This study represents the first systematic review covering data over a 75-year period and examining the impact of OBEs on educational outcomes, students' emotional state, and cognitive development. Practical Significance. The findings highlight the potential of OBEs as a tool for improving the quality of education and preparing students for professional activities, especially when implemented thoughtfully.