Relationship building and minority business growth: Does participating in activities sponsored by institutional intermediaries help?

•Minority businesses can increase firm growth from their membership in a minority-supporting institutional intermediary.•Minority businesses’ active participation in intermediary-sponsored activities is important for building relationships with both corporate members and with other minority members.•Participating more in connect-oriented activities versus develop-oriented activities increases relationship building with other minority members.•Effects of relationship building with corporate members increase when minority businesses had government contracting experience.•While effects of relationship building with other minority members vary across ethnicity groups.