In sheer quantity, the five original BRICS countries appear impressive. They account for a substantial share of the world's population, economy, trade and muster large militaries. In January 2024, BRICS gained even more steam, by admitting four new member states that participated in the most...

I study a repeated principal-agent game with long-term output contracts that can be renegotiated at will. Actions are observable but not contractible, so they can only be incentivized through implicit agreements formed in equilibrium. I show that contract renegotiation is a powerful tool for...

We study a communication game between an informed sender and an uninformed receiver with repeated interactions and voluntary transfers. Transfers motivate the receiver's decision-making and signal the sender's information. Although full separation can always be supported in equilibrium, partial...

We study a repeated principal-agent model with transferable utility, where the principal's evaluation of the agent's performance is subjective. Our focus is on equilibria which are robust to the addition of small privately observed shocks to the payoffs. Existing constructions of positive-effort...

A principal incentivizes an agent to maintain compliance and to truthfully announce any breaches of compliance. Compliance is imperfectly controlled by the agent's private effort choices, is partially persistent, and is verifiable by the principal only through costly inspections. We show that in...

Joining the EU requires not only that candidate countries fulfil a certain number of conditions, but also that EU countries feel ready to welcome new members.

Russia's unprovoked and unjustified full-scale invasion of Ukraine has significantly changed the geopolitical circumstances on the European continent and is also importantly reshaping the EU's enlargement policy.

This paper explains why the approach taken so far to mitigate global climate change has failed. The central reason is an inability to enforce targets and timetables. Current proposals recommending even stricter emission limits will not help unless they are able to address the enforcement...

As a major trading power in the world, the European Union is an important trading partner for five emerging economies, namely Brazil, Russia, India, China and South Africa (the BRICS countries). The EU is particularly interested in protecting the interests of developing countries and supports...