The Nobel Prize-winning chancellor of Cardiff University has stepped down after eight years in the role.
Sir Martin Evans said it had been an "honour and a privilege" to watch students graduate from the university in the ceremonial role since 2009.
In 2014, a bid to appoint comedian Griff Rhys Jones as the chancellor was stalled at the last minute which led to Sir Martin taking up a second term.
The university said the appointment process would begin in "due course".
Sir Martin, who won the Nobel Prize for Medicine in 2007, was the 22nd chancellor of the university - a ceremonial role, chairing the annual general meeting and presiding at graduation ceremonies.
He will remain part of the university as emeritus professor, an honorary title recognising distinguished academic service.
In 2013, the university named the School of Bioscience building in his honour.
Prof Colin Riordan, the university's vice-chancellor, said: "Professor Sir Martin Evans holds, to date, the only Nobel Prize to have been won by a scientist working in Wales and this is a matter of immeasurable pride for the university.
"We are grateful for his immense contribution to science, the wide ranging benefits of his research and his service to the university."