Roedd y broses recriwtio ar gyfer rôl yr Ysgrifennydd Parhaol yn cynnwys cyfweliad panel gydag Ysgrifennydd y Cabinet a Phennaeth Gwasanaeth Sifil y DU, Syr Jeremy Heywood, ac uwch gynrychiolwyr o’r llywodraeth a thu hwnt. Gwnaed y penodiad gan y Prif Weinidog mewn cytundeb â Syr Jeremy, a ddywedodd:
The recruitment process for the Permanent Secretary role included a panel interview with the Cabinet Secretary and Head of the UK Civil Service, Sir Jeremy Heywood and senior representatives from within and outside government. The appointment has been made by the First Minister in agreement with Sir Jeremy, who said: