Pros
The knowledge that you're helping children in need. Most of the people at the company are passionate and very, very enthusiastic about social justice, women's issues and social issues, and have the energy to inspire others to help make things better in their community and the world at large. Working at Unicef means constantly being educated about world politics and problems, so it's not necessarily for someone who wants a set routine. The people are also keen on environmental issues, so offices tend to be very green and staff do so on a budget, ex. paper is printed on both sides; post-its are reused until they're ready to fall apart; heavy-duty curtains and caulking take care of drafty windows instead of full-blast heaters.
Cons
It's all contract work with no benefits unless it's a long contract, so Unicef saves money. Year round job opportunities don't exist unless you're living in the city where the main national HQ is. Even supervisors are hired on contracts so there's always this crazy learning curve where everyone adjusts to new staff frequently due to new staff coming on board and "old" (meaning more than 3 months) staff leaving as their contracts end. As a result, training can be sub-par depending on the manager. Screw ups on paycheques are normal, and you're not compensated for using your cell phone to do company business outside office hours, and getting overtime pay is as tough as scaling Mt. Everest without a Sherpa guide. Don't count on a job reference after your contract is up, as most likely your manager will be gone too as his or her contract ends, or you may have worked with 3 supervisors in 3 months. Work hours can be sporadic depending on the department's budget.