T-group stands for training group. As far as we know this leads back to Kurt Lewin and refers to the beginning of group-dynamic research. One created special settings (amongst others K. Lewin in the USA, W. Bion and others in Tavistock, UK) in which one skilfully began to examine the dynamics of groups, particularly also aggressive behaviour.
The framework consisted of bringing together a group of strangers for a few days, without a shared task and without a pre-determined structure. This happened without firmly laid-down meeting times and without formal leadership. Observers (the group-dynamic ‘trainers’) then openly fed back to the group their thoughts about the events. They talked about developing informal roles, about conflicts, about blind spots, they gave feedback. This was discussed by the group and led to renewed effects in the interaction patterns. Thus, each group participant had to engage with their effect, with coalition formations, with sympathies and rejection and with being influential and conceding influence. This liberated very strong emotions, but also led to much hurt and destructive developments which, in principle, are not necessary to discover something about oneself in groups.
As problematical and open to criticism the setting is, it delivered interesting insights about self-organisation principles in groups. The theory of team dynamics, presented here, is also affected in many areas by the findings and influencing techniques of the self-organisation, i.e. it builds upon it. The ability to perceive complexity, in particular, can be learned and practiced in the management of such groups.