If interpersonal relationship problems are the core of all psychopathology, it follows that a primary focus of group therapy would be the strengthening of interpersonal relationship skills
Learning from the in-group interpersonal experience, where group members use the group as a place to identify and revise problematic relationship tendencies
Characteristics that would cause a group therapist not to select a prospective member include those that would interfere with the client's ability to interact meaningfully with others and reflect on that interaction, such as psychosis, organic brain damage, acute crisis, and pragmatic issues such as travel or transportation that would interfere with regular attendance.
Initial stage: Clients are cautious and concerned about whether they will be accepted into the group
Second stage: There is some competition or jockeying for position within the social pecking order
Third stage: Cohesiveness forms, members feel closely connected and trusting of one another, and the group sessions become more consistently productive as clients learn about and improve on their interpersonal skills
Cotherapists don't trust each other, compete with each other, or "step on each other's toes" by approaching group therapy with incompatible therapy orientations
Clients who socialize with one another outside therapy groups can become more loyal to their friendship than they are to the group as a whole, be reluctant to comment frankly on each other's behavior in front of the group, and save their most direct, meaningful exchanges for private moments rather than sharing them during group sessions.
The consequences of one client violating the confidentiality of another can seriously affect the professional or personal life of the client whose confidentiality has been violated, and such breaches make the therapy group seem unsafe and untrustworthy, which decreases self-disclosure by other clients.
Group therapy is superior to no treatment and generally as effective as individual therapy, although a minority of comparative studies have found individual therapy to be slightly superior.
Cohesiveness within the group, much like the therapeutic relationship in individual therapy, is a major contributor to successful outcome in group therapy.