Are humans fair by nature? Why do we often willingly trust strangers or cooperate with them even if those actions leave us vulnerable to exploitation? Does this natural inclination towards fairness or trust have implications in the market-place? Traditional economic theory would perhaps think not, perceiving human interaction as self-interested at heart. There is increasing evidence however that social norms and norm-driven behaviour such as a preference for fairness, generosity or trust have serious implications for economics. This book provides an easily accessible overview of economic experiments, specifically those that explore the role of fairness, generosity, trust and reciprocity in economic transactions.