The concept of "trigger" in recent decades has become widely used in domestic and world theory and practice of conflict. However, this term has not yet received in-depth scientific reflection and is used arbitrarily. What is a trigger, what are its components, and how is it fundamentally different from other conflict phenomena – causes, conditions, and many other phenomena of a complex conflict system? This article is an attempt to conceptualize and categorize the concept of a trigger in order to further use it for scientific description and analysis in the plane of practical work with conflict.