We study the implementation problem for exchange economies when agents can renegotiate the outcome assigned by the planner and can collude. We focus on the use of sequential mechanisms and present a simple sufficient condition for implementation with renegotiation in strong perfect equilibrium....

To what extent a taxing authority should be granted the power to impose different tax schedules to different groups of taxpayers? Although the policy maker aims at maximizing social welfare, her tax policy may be distorted by the lobbying activity of taxpayers. In this political environment we...