We propose a theory of supervision with endogenous transaction costs. A principal delegates part of his authority to a supervisor who can acquire soft information about an agent's productivity. If the supervisor were risk-neutral, the principal would simply make the better informed supervisor...

This paper discusses the origins of the transaction costs in side-contracting. In Tirole (1986)'s model of collusion with a risk averse supervisor, the optimal collusion-proof contract trades-off coalitional incentives against an insurance motive. We characterize the corresponding agency cost...