Pros
Meeting people from different cultures
Cons
There are a lot of cons but the main one, specially if you're coming from the private sector, is to see so much mismanagement of funds, overhead and waist. You will be choked and somewhat disgusted about it. There are two types of people there: the ones that care and work hard to fulfill WFP's mission and the ones that are there for the benefits. If you're part of the first group, the later will make your life a nightmare. The work enrichment is terrible. Example about how bad things are: the other they launch a campaign about 'respect'. If you're looking for some bureaucratic career where you sit in useless status meetings 80% of your day while making some money at the expense of beneficiaries, this is the place for you. It is hard to adapt if you're coming from the private sector, specially if you're coming from outside Italy.