The intention of the thesis is to conduct a research on influence of diplomatic flows between decision makers of individual countries and regimes of these coutries, in crises directly before the start of the World War One. Thesis is found around the key question, how did communications between individual actors and their decisions influence the development of events which led to World War One. The reason behind interest of conducting a research on this historically distant subject, can be found in fact, that this period offers us great diversity of regimes and consequently interstate divisions of power and systems of decision-making and from the other perspective also very specifical communicational mechanisms with various characteristics. As we research the events of pre-World War One crisis, we can encounter both – intetional denial or crippling of diplomatic communications, as we also encounter unintentional denial or crippling of diplomatic communications. Thesis consist of two parts – in theoretical I am trying to define the concept of crisis comunication and decision-making as part of crisis management, while I also need to mention communication-information technology and other means of information transfer, as they are crucial for communication itself. Up next I am also defining the concept of regimes, and point out key specific characteristics regimes of time. In second, empirical part, I will use descriptive analysis of secondary and tertiary sources to try to describe the connection between decisions of superpowers and their circumstances and regimes and diplomatic flow. I will emphasize my research on goals of each decision-maker when making decisions, availability of means of crisis communication and reaction to pre-made decisions of other actors.