Diversity is a common factor in many organizations. Diversity is categorized into two levels, surface and deep; while the former impedes the performance of individuals and groups, the latter improves it. Although existing research discuss each of these aspects, the effects of their interaction have not been sufficiently explored. In addition, management of the relationship between diversity and performance has not been discussed in-depth. Recent studies have shed light on the concept of “inclusion” in the area of diversity management. The purpose of this study is to examine empirically how inclusion enhances an employee's work motivation.
How workplace diversity influences an employee's behavior and how inclusion works in an organization are explained through the social categorical theory, and we have derived hypotheses based on this theory. Data to test the theoretical model were collected through panel survey to avoid common method bias. The findings are as follows: (1) inclusion behavior from organizational management enhanced the degree of an employee's identification with his/her organization; (2) when organizational identification was high, both surface-level and deep-level workplace diversity positively influenced cooperation-oriented motivation. Additionally, surface-level diversity increased deep-level diversity. However, when organizational identification was low, surface-level diversity decreased cooperation-oriented motivation. Inclusion behavior enhances organizational identification, and thus indirectly manages employees' cooperation-oriented motivation.