Retired Marine General John Kelly has been sworn in as the new White House chief of staff. Kelly formerly headed President Donald Trump’s Department of Homeland Security.

The general is expected to bring order to the West Wing after last week’s staff shakeup. Trump announced his appointment on Friday afternoon, after accepting the resignation of Reince Preibus, former GOP chairman who served as the White House chief of staff since the inauguration in January.

Kelly will do a “spectacular” job, Trump told reporters after the swearing-in on Monday.

The chief of staff’s departure came a week after Sean Spicer resigned as White House press secretary. He was replaced by his deputy, Sarah Huckabee Sanders, while financier Anthony Scaramucci was brought on as the new communications director.