The paper brings research findings concerning the "concentration of attention" as one of the basic preconditions for successful work with "Advanced automated command and control systems" (PASVŘ) in the environment of the Armed Forces of the Czech Republic. The main aim of the research was to determine the level of attention and concentration differences among the future users PASVŘ in the context of selected mental states before and after stress. The research sample consisted of 170 respondents -students of military branches of University of Defense. The research came to interesting results. In the situation immediately after the stress occurred an increase in the number of solved problems and also in their accuracy.