What are the career options for an MBA-Strategy student (graduating from top business school in US) in International organizations like United Nations, World Bank etc.?

Limited. These organizations attract--for whatever reason--the "best" from various countries.  This is possibly because of two reasons: Resume chum - Having the name "World Bank" and "UN" on a resume is a great name to drop.  Many doors open in life once you're "on the inside".  This is probably the most common reason. A genuine passion - These organizations do provide a very critical and high level of service to their stakeholders.  Being at the "center" of things is a powerful feeling.  Many people like that feeling. I have a friend with a TOP NOTCH education from a great school, who's father is well connected (he states that he didn't use those connections, so kudos to him) who struggled getting into several low-level US government jobs.  He finally got one, but he had to cycle through professional temp and contract jobs until he had enough of a resume to impress the hiring people at State.  Why?  The US government has been actually down-sizing some departments and freezing most of all others.  It's a tough job market, and you really need to set yourself apart. The same thing is happening at every other first world government institution.  Where are all these people going who cannot find jobs or who had them and lost them?  Anywhere they can, including the World Bank, UN, OPEC, NATO, IMF, other NGO's and corporations too. I'm not saying you can't get a job there, it's just that--in my opinion--you'll have to do a little better than an MBA from a great school. What are your connections? How many languages do you speak?  Critical ones (English, obviously), but what about Mandarin, Spanish, Russian, French or Arabic? What kind of job experience do you have?  Is any of it relevant or leverage-able for the jobs you want? Do you have any form of US security clearance? Where have you interned? What fraternities/sororities are you a part of? Do you have any other specialties / degrees that can enhance your resume? What were your grades like? Any other reasonably notable college accomplishments? Best of luck to you.

It's impossible to answer without knowing what sort of work you would like  to do, where you would like to work and where you're able to work (language, visa restrictions), your long-term aspirations (money? doing the right thing? travelling?), what's important to you (money? doing the right thing? travelling? changing the world?) Your best bet is to look at those organisations' career sites and see their requirements for candidates - for the UN it's https://careers.un.org/lbw/home.aspx?viewtype=WWLF world bank at http://wwwr.worldbank.org/jobs I hope you find what you want.