ABSTRACT
In the ®rst section, we consider the connection between groups and their environment. One way in which groups connect with their environment is through interactions with people outside the group. For example, a member of an organizational team may interact with members from other teams, higher management, and clients. These interactions often involve the exchange of certain resources such as money and information (cf. social exchange; Chapter 1). This topic will be discussed under the label of boundary-spanning activities. Besides the exchange of resources with people outside the team, groups are open systems in another way. Not only can resources (such as information) ¯ow to and from groups, but sometimes old members leave and new members enter groups. We also consider some consequences of membership change.
