In system dynamics, we use the term “mental model” to describe one’s perceived structure of system. We care about mental model, because it is what we attempt to describe, understand, and improve using computer simulation models. But if we are developing our simulation models from a group of individuals, can we still call what we are trying to study a mental model? This paper attempts to define the concept parallel to mental model that can be applied to group environment. In order to discover a group-level mental-model-like concept that is grounded in the established literature, this study surveys various terminologies and definitions used in the literature to describe the similar concepts. The survey reveals that there are subtle differences among the concepts discussed, and the conceptual differences are highlighted by using location and form of the processor as criteria. This finding leads to an insight that what system dynamics modelers try to understand, represent, and improve in group intervention processes is not one single concept. Depending on data collection and integration methods, the concept can vary in terms of location and form.