Pros
Nice building. If you are in a programme department, you meet various stakeholders from many different countries. Projects and partners may save you from insanity inflicted by internal psychosis.
Cons
Mostly incompetent people in key positions especially in (top) management and HR. The (top) management being seconded by the governments of member countries makes it a joke especially when these people are diplomats. They seem to have been dropped at ASEF either because they are reaching retirement age or their governments discard them for a while for various reasons. The only thing they are good at is bureaucracy thus paralysing the organisation. No vision, crap leadership if any, no respect, no recognition (unless you forget about your neurones and simply become a brown noser or cheerleader such as the chief of staff for instance), badly compensated, no training and NO TRUST. As it is, it’s no place for experienced people. For less experienced, don’t stay more than 2-3 years because you’ll lose touch with the world out there.