In determining how he will behave, an actor must try to predict how others will act and how their actions will affect his values. The actor must therefore develop an image of others and of their intentions. This image may, however, turn out to be an inaccurate one; the actor may, for a number of reasons, misperceive both others’ actions and their intentions. In this research note I wish to discuss the types of misperceptions of other states’ intentions which states tend to make. The concept of intention is complex, but here we can consider it to comprise the ways in which the state feels it will act in a wide range of future contingencies. These ways of acting usually are not specific and well-developed plans. For many reasons a national or individual actor may not know how he will act under given conditions, but this problem cannot be dealt with here.