This article is an extensive review of literature on crisis intervention. The authors explore the theoretical grounds of this approach and rate them by means of a thorough analysis of the research done on the subject. More precisely they elaborate a definition of a crisis, provide a classification of same, explain its process and describe how the intervention develops in a crisis situation. They examine, in the second part, the dependence phenomenon, and the determining factors encountered. Then, they study the notion of the triggering factors that lead them to the necessity of taking into account the mediatory factors and explanatory variables in the resolution of the crisis.