The interview process is a bit of a front. They're required to make it look like they're publicly advertising for a post and reviewing multiple candidates, even if they already have one person in mind. I was referred into the consultancy, but still had to go through the interview process, which was sending in standard materials to the potential employer, and then having a panel interview over Skype. Fairly easy interview because, again, it was a formality. Be cautious when applying to UNICEF posts, because they may or may not be actively looking for new applicants.