Yerbi Fandau

Doctor Yerbi Fandau was the head of Starfleet Medical until 2379. In 2378, he contacted Beverly Crusher aboard the USS Enterprise-E and told her that he would be retiring the next year and offered her the position as his replacement.

As per standard protocol, Fandau also contacted Crusher's commanding officer - Captain Jean-Luc Picard to inform him of the offer. It took Crusher almost a full year to decide, but eventually she did accept the position and took over for Fandau in late 2379. (TNG novels: A Time to Be Born and A Time for War, A Time for Peace.