During the last two decades economists have made much progress in understanding incentives, contracts and organisations. Yet, they constrained their attention to a very narrow and empirically questionable view of human motivation. The purpose of this paper is to show that this narrow view of...

We show experimentally that fairness concerns may have a decisive impact on both the actual and the optimal choice of contracts in a moral hazard context. Explicit incentive contracts that are optimal according to self-interest theory become inferior when some agents value fairness. Conversely,...