The typical collective memories of societies involved in intractable conflicts play a major role in the eruption and continuation of the conflicts, whereas the positive transformation of these memories to being less self-serving promotes peacemaking. A major factor that inhibits such transformation is self-censorship. Self-censorship, practiced by members of a society's formal institutions, inhibits the dissemination of alternative, more accurate narratives of the conflict that may change dominating biased conflict-supporting memories. Despite the importance of formal self-censorship in maintaining collective memories of conflicts, little empirical and theoretical research has examined this phenomenon. The present study addresses this omission. It examines the self-censorship practiced from 1949 to 2004 in 3 formal Israeli institutions (the National Information Center, the IDF/army, and the Ministry of Education) regarding the main historical event of the Israeli-Palestinian conflict: the causes of the 1948 Palestinian exodus. This is done by analyzing all of these institutions' publications produced throughout the 56-year research period and interviewing their key position holders. The results show that the institution gatekeepers practiced self-censorship for 5 reasons: garnering international support, mobilizing citizens, the impact of Zionist ideology, institutional norms, and fear of sanctions. The empirical findings are used to elicit theoretical insights, such as a definition for formal self-censorship, the difference between self-censorship practiced by gatekeepers (from formal and informal institutions) and that practiced by ordinary individuals, the 5 reasons for such self-censorship.