Pros
The people are great to work with since everyone's dedicated to the cause. That being said, oftentimes people are expected to work late/on weekends without getting overtime (unless you're in Accounting where you WILL work overtime whether you want to or not!), and at the low salaries they give you it may not be worth it to some. We're also currently going through some growing pains -- more "red tape" and "politics" are coming into play as our organization has grown a lot in the past few years -- but hopefully these will smooth out over time. Benefits are very good, although the pension plan is no longer offered so that stinks for new employees.
Cons
Low salary; workload balance isn't always in play (some people have very little work while others work overtime all the time); IF you're in the right dept., work-life balance is good, but if you're not then it can be tough.