Conclusions 499fundamental mission: developing a comprehensive model of
social conflict, harmony, and integration.
We propose that understanding how structural, social, and
psychological mechanismsjointlyshape intergroup relations
can have both valuable theoretical and practical implications.
Theoretically, individual difference (e.g., social dominance
orientation; Sidanius & Pratto, 1999), functional (e.g., Sherif &
Sherif, 1969), and collective identity (e.g., Tajfel & Turner,
1979; Turner et al., 1987) approaches can be viewed as com-
plementary rather than competing explanations for social con-
flict and harmony (see Figure 20.1). Conceptually, intergroup
relations are significantly influenced by structural factors as
well as by individual orientations toward intergroup relations
(e.g., social dominance orientation; Sidanius & Pratto, 1999)
and toward group membership (e.g., strength of identifica-
tion) and by the nature of collective identity. Functional rela-
tions within and between groups and social identity can
influence perceptions of intra- and intergroup support or threat
as well as the nature of group representations (see Figure 20.1).
For instance, greater dependence on in-group members can
strengthen the perceived boundaries, fostering representations
as members of different groups and increasing perceptions of
threat (L. Gaertner & Insko, 2000). Empirically, self-interest,
realistic group threat, and identity threat have been shown in-
dependently to affect intergroup relations adversely (Bobo,
1999; Esses et al., 1998; Stephan & Stephan, 2000). Percep-
tions of intergroup threat or support and group representations
can also mutually influence one another. Perceptions of com-
petition or threat increase the salience of different group repre-
sentations and decrease the salience of superordinate group
connections, whereas stronger inclusive representations of the
groups can decrease perceptions of intergroup competition
(S. L. Gaertner et al., 1990).
Similarly, within the social categorization approach, re-
searchers have posited not only that decategorization, recate-
gorization, and mutual intergroup differentiation processes
can each play a role in the reduction of bias over time
(Pettigrew, 1998a), but also that these processes can facilitate
each other reciprocally (S. L. Gaertner et al., 2000; Hewstone,
1996). Within an alternating sequence of categorization
processes, mutual differentiation may emerge initially to neu-
tralize threats to original group identities posed by the recate-
gorization and decategorization processes. Once established,
mutual differentiation can facilitate the subsequent recogni-
tion and acceptance of a salient superordinate identity and
recategorization, which would have previously stimulated
threats to the distinctiveness of group identities (S. Gaertner &
Dovidio, 2000).
Reductions in perceived threat, increased perceptions of
intergroup support, and more inclusive representations (either
as a superordinate group or as a dual identity), in turn, can
activate group- and individual-level processes that can reduce
intergroup conflict (see Figure 20.1). These processes may
also operate sequentially. For example, once people identify
with a common group identity, they may be more trusting of
former out-group members and consequently be willing to en-
gage in the type of personalized, self-disclosing interaction
that can further promote social harmony (Brewer & Miller,
1984; Dovidio et al., 1997). Thus, factors related to structural
and functional relations between groups and those associated
with collective representations (e.g., involving mutual inter-
group differentiation, recategorization, and decategorizationFigure 20.1 The roles of functional and identity relations in social conflict and integration.