Social Capital is the value embedded in social networks — the relationships, trust, reciprocity norms, and shared expectations that enable cooperation and collective action. Robert Putnam's foundational research showed that social capital is a major predictor of economic development, health outcomes, and institutional effectiveness. Pierre Bourdieu distinguished social capital from economic and cultural capital as a separate but equally real form of wealth.
The Trust Equation is David Maister, Charles Green, and Robert Galford's framework for understanding and building trust in professional relationships. Trust = (Credibility + Reliability + Intimacy) / Self-Orientation. Each variable has a specific definition and levers for improvement. Self-orientation — being focused primarily on your own interests — is the trust-destroyer; it sits in the denominator, meaning even high credibility, reliability, and intimacy are undermined by visible self-interest.