The European University Viadrina at Frankfurt (Oder) is, due to its location on the German-Polish border and its high rate of international students (40 %), a place predestined to explore the subject of intercultural communication. However, the students in fact do not notice the interculturalism in their everyday lives. German and Polish students form two big groups which are distant from one another and the communicative interaction is very limited. As former studies have already asserted, the contact hypothesis works only under special conditions. The origins of the group formation and the mutual lack of interest are complex. This study especially considers one of all possible aspects and analyses it: failed communication caused by cultural differences. With the analysis of the Critical Incidents, several characteristic fields of culturally-caused conflicts between German and Polish students were able to be identified. (author´s abstract) / Series: WU Online Papers in International Business Communication / Series One: Intercultural Communication and Language Learning