From Tar Valon Library
The First Selector is the Blue Head of Ajah. during and immiedaltey after the Aiel War, the First Selector was Eadyth. It is unknown who the current First Selector is. As with most Ajah titles, it is a closely guarded secret (NS, Ch. 11). The first selector is not usually a Sitter, but it does happen (NS, Ch. 11).