In order to examine the process of our interaction with others, G. H, Mead's theory of interaction or "a conversation of gestures" is investigated. First, how Mead describes the process of interaction and how he defines and uses the term are examined. According to him, the process of interaction can be described as a conversation of gestures. Then, what is a conversation of gestures? To answer this question, the concept of "gesture" and the distinction between "(non-vocal) gesture" and "vocal gesture" are studied. Mead's definition of "gesture", its social behavioristic implications, and the function of gestures as mutual adjustment are presented. It is discussed that the distinction between those two kinds of gestures is not in their vocality, as explained by Mead himself, but in their "simultaneous-reflexivity" from the standpoint of the actor, and that, in spite of this distinction, each gesture that mediates a conversation is a united whole including both vocal (simultaneously-reflexive) part and non-vocal (non-simultaneously-reflexive) part as observed from the standpoint of others. Finally, the implications of the conception of interaction as a conversation of gestures are discussed, and further themes concerning this conversation, gestures and our process of adjustment are offered for future studies in our social interaction.