Mutism is a symptom we see in consultation for an absence or lack of langage acquisition and/or for relationship problems (isolation, withdrawal, crisis when breaking up) alerting the family. The differential diagnosis is complex and mutism can be symptomatic of several personality psychopathological structures. After a literature review, we shall describe three clinical cases and discuss the difficult approach to this symptom, its psychopathological features, as well as its pronostic and therapeutic aspects".