Inclusion
Inclusion is the engagement, respect, and support of individuals in a group such as a team, company, or governing body. If diversity is "having a seat at the table" then inclusion is "having a voice at the table." An environment is considered "inclusive" when individuals from distinct cohorts report similar ability to share ideas with their peers and leadership.
A common rule to ensure an environment is inclusive is that "if you're not intentionally including, you're probably accidentally excluding."
Broader Topics Related to Inclusion

Social Justice
The balance of opportunity and wealth distribution in a society