We know this is true for our personal lives; our romantic partners, kids, parents, and best friends are tremendous sources of happiness. The Importance of Cross-Class Friendships for Career SuccessAs it turns out, friendships are valuable sources of career capital. The results were profound: Having economic cross-class friendships was vital to future income. Yet the authors also found that intraclass friendships were crucial to future economic success, particularly amongst lower-income people. Cross-class friendship was a significant and positive correlate of upward mobility, meaning people with richer friends had better economic outcomes themselves.