When a face-to-face work group tries to accomplish its collective goals, the effectiveness and maturity of a group hinge on the combination of the functional roles performed by group members¡X task-oriented roles and group maintenance roles [Klopf, 1981; Benne et. al., 1948]. This research examines the phenomenon of group developmental processes, the functional roles performed by group members, and the relationships among certain critical functional roles, group maturity, and team effectiveness in the learning-task oriented virtual team setting. The samples are 24 project teams composed by part-time graduate students in a cyber university. After analyzing the group discussion sections by content analysis method, the development processes of these virtual teams demonstrate Tuckman¡¦s five-stage model of group development: forming, storming, norming, performing and adjourning. For the groups on forming stage, there are only two group maintenance roles ¡X initiator and information seeker/giver, performing by virtual team members. Conflicts between team members are not obvious due to virtual teams¡¦ learning-oriented task. Three group maintenance roles ¡X encourager, gatekeeper, and follower will encourage the occurrence of group cohesiveness and lead virtual teams to norming stage. Furthermore, when groups mature, four emerging task-oriented roles ¡X opinion seeker/giver, coordinator, orienter and evaluator will enhance the virtual team effectiveness. Negative functional roles (process-hindering roles) are rare due to virtual team¡¦s learning-oriented task. Therefore, this result indicates that members in a virtual team should play different critical positive functional roles according to their group¡¦s developmental stages, and it will facilitate group evolvement and improve team effectiveness.

Facing the unceasing challenges of new technology, the use of virtual teams as the future organization structure has become more and more common. The objectives of this thesis are to investigate members¡¦ behavior in each stage of group development adopted from Tuckman¡¦s five-stages model, and to find out the impact of critical behaviors on virtual team¡¦s collaborative performance. This thesis selects nine learning-task oriented virtual teams composed by part-time graduate students in cyber university of NSYSU and probes into the theme of each groups¡¦ discussions by content analysis approach. SYMLOG is applied to observe group member¡¦s behavior and construct the categories of content analysis. According to the research results, the critical behaviors of initial stage are active (U) and friendly (P) behaviors. During the middle stage, the existence of encouragers and followers should improve group development towards high performance. In the final stage, group members shall be able to shift the communication focus from emotionally expressive (B) to instrumentally controlled (F) in order to reach superior effectiveness. Therefore, the findings of this thesis will provide some suggestions about member¡¦s behavior, facilitate group development, and improve virtual team¡¦s collaborative performance.