The concept of "integration" involves the idea of having a sense
of belonging to a group. In other words, if someone is well-integrated into a group they see
themselves as being a part of that group (in terms of such things as
norms, values, roles and so forth).
A well-integrated individual cares for both the group as a whole and its individual members - which makes over-integration a real problem for participant observers since they need to retain some sort of objective distance from the group if they are to validly observe it...