Play therapy is a technique whereby the child's natural means of expression; namely play, is used as a therapeutic method to assist him/her in coping with emotional stress or trauma. Play Therapy is often used as tool of diagnosis. A psychologist observes a client playing with toys (play-houses, pets, dolls, etc.) to determine the cause of the disturbed behavior and/or underlying problem. The objects and patterns of play, as well as the willingness to interact with the therapist, can be used to understand the underlying rationale for behavior both inside and outside the session
Practitioners of play therapy believe that this method allows the child to manipulate the world on a smaller scale, something that cannot be done in the child's everyday environment. By playing with specially selected materials, and with the guidance of a person who reacts in a designated manner, the child plays out his/her feelings, bringing these hidden emotions to the surface where s/he can face them and cope with them.