This paper provides new analytical tools for studying principal-agent problems with adverse selection and limited commitment. By allowing the principal to use general communication devices we overcome the literature's common, but overly restrictive focus on one-shot, direct communication. In...

I study the optimal audit mechanism when the principal cannot commit to an audit strategy. Invoking a relevation principle, the agent reports her type to a mediator whi assigns contracts and recommends the principla whether to audit. For each reported type the mediator randomizes over a...

We study a principal-agent model with moral hazard and adverse selection. Risk-neutral agents with limited liability have arbitrary private information about the distribution of outputs and the cost of effort. We show that under a multiplicative separability condition, the optimal mechanism...