Pros
Great place to learn about Latin America. Interesting projects. Good salary - excellent benefits. Access to governments and companies throughout the region. The name opens doors. Stay a few years but don't stay too long unless you are a political animal and dont believe in a merit-bases world.
Cons
The IDB is highly political in the worst possible way. In the reorganization of the private sector, the people heading the transition team awarded themselves the top jobs and the new head of investments proceeded to liquidate all the existing management and retain her cronies. HR set up bogus interview panels that all received instructions from the same person. The career management system is a joke - it all depends on who you know not what you know.