Donald Trump has named the acting heads of national-security agencies—all career federal executives—to serve until Senate-confirmed nominees are in place, according to a White House press release issued soon after the inauguration on Monday.

As one of his first acts, President Donald Trump appointed 31 people to lead various government agencies on an acting basis while his Cabinet nominees move through the Senate confirmation process. The list of people Trump approved on Monday after he was sworn in will carry out the first acts of Trump’s second term.

President Trump is tapping a number of officials to serve as acting department heads as he waits for the Senate to confirm his Cabinet nominees. While some acting heads will only serve for a short time until their permanent successors are confirmed,