Many optimal contracting papers use quasi-linear preferences. To exclude stochastic mechanisms they impose a (su cient) condition on how the curvature of an agent's objective function varies with type. We show with quasi-linear preferences that an optimal deterministic outcome without bunching...

The single crossing assumption simplifies the analysis of screening models as local incentive compatibility becomes sufficient for global incentive compatibility. If single crossing is violated, global incentive compatibility constraints have to be taken into account. This paper studies monotone...