The equilibrium model of group development (equilibrium model) was created by Robert Bales, a pioneer of the empirical studies on group development. The equilibrium model posits that members within a group struggle to maintain a balance between task-oriented (instrumental) and socio-emotional (expressive) needs. The equilibrium model was the first extensive and systematic description of group development borne out of group observation. The equilibrium model is classified as a progressive model as it explains group maturity and performance over a given period of time. Bales’ equilibrium model was proposed as a means to study the manifestation and incidence of task-oriented and socio-emotional behaviours within groups.
Contents
Stages
There are three main progressive stages within the equilibrium model. The first stage is the orientation stage which refers to the initial instance where the group members meet. In this exploratory stage, members ask questions and exchange information with one another, and task-oriented behaviours are prevalent. The second phase of the equilibrium model is the evaluation stage and refers to when group members express their opinions and attitudes. In the evaluation stage, socio-emotional behaviours increase among the group members. The third phase of the equilibrium model is the control stage. Within the control stage, group members exert pressure in order to influence group actions and activities. Overall, as a group moves throughout the three progressive stages, task-oriented behaviours decline while socio-emotional behaviours increase
Successful group performance and cohesiveness is achieved once a group has matured and the members are able to maintain equilibrium between how well they can solve the task or problem facing the group (task-oriented behaviours) with how well they deal with interpersonal relationships and member satisfaction (socio-emotional behaviours). However, equilibrium may be temporary; for example, as the group encounters a new situation or takes on new members, the group may need to move through the three progressive stages once again.
Application
Bales’ equilibrium model has been applied to research in a number of areas including computer-mediated communication (CMC) and educational psychology.