Saturday will mark the one-year anniversary of President Donald Trump’s inauguration — but Trump’s first year in office hasn’t been backed up by a full executive branch staff.

The Trump administration will usher in the second quarter of its presidential term with hundreds of vacancies still left to fill in departments throughout the administration. According to the Washington Post and Partnership for Public Service, only 241 key positions requiring Senate confirmation — out of 633 — have been confirmed as of Jan. 18, with 244 positions still without a nominee. The 633 key positions are a small portion of over 1,200 total positions requiring Senate confirmation, the Post noted.

Trump’s sluggish staffing stands in stark contrast to his predecessors. According to the Post, Trump had 301 total confirmed nominees by Jan. 18, as compared with 452 confirmations by former President Barack Obama, 493 by George W. Bush and 471 by Bill Clinton at the same point in their terms.

Trump’s nominations have also taken 72 days to confirm on average — far slower than his predecessors’ averages, which ranged between 36 and 54 days. For a nominee to be confirmed, they must first undergo background checks by the FBI and Office of Government Ethics before being sent to the Senate for vetting and a final confirmation vote.

Part of the Trump administration’s numerous vacancies, the president claims, are by design. Trump has frequently decried the numerous White House staffing positions as government waste, saying in an October interview with Forbes that his administration “[doesn’t] need as many people.”

“I’m generally not going to make a lot of the appointments that would normally be — because you don’t need them. I mean, you look at some of these agencies, how massive they are, and it’s totally unnecessary. They have hundreds of thousands of people,” Trump told Forbes.

Experts, however, say that simply not staffing his administration doesn’t work the way Trump claims.

“There is a legitimate case to be made for de-layering government, for reducing the number of political employees, but you have to do that intentionally,” Max Stier, president of the Partnership for Public Service, told the Guardian. “Failing to nominate people in a reasonably quick fashion isn’t the same as intentionally deciding, saying that you want to remove certain jobs from government so that you can make it more streamlined. The latter would be, I think, welcomed.”

Many of the vacant positions, NPR noted in October, are temporarily filled by career civil servants, who experts said may be more tentative and risk-averse than political appointees.

These civil servants, Stier explained to NPR, are “the proverbial substitute teacher; everyone knows you’re not around for the long term. Whatever decisions you make aren’t going to necessarily stick. You’re not likely to take the long-term view or handle the most difficult issues.”

Furthermore, these interim employees’ tenures are now surpassing their legal limits. NPR reported in November that the Federal Vacancies Reform Act gives presidential administrations 300 days to fill political appointments, in order to prevent administrations from simply circumventing the Senate confirmation process by appointing someone to an acting role indefinitely. Trump’s administration has blown past the 300-day mark, meaning that decisions made by an employee in an acting capacity could be subject to a court challenge as being improperly made.

Additionally, while Trump claims to be eliminating waste by not staffing many of these positions, many of the unfilled positions actually serve critical functions in the federal government. Here are just 10 of the important positions that still don’t have a nominee, according to the Post’s database.

Administrator of the Drug Enforcement Administration

As Attorney General Jeff Sessions attacks the legalization of marijuana, the U.S. Department of Justice is going without a permanent head of the department responsible for the country’s drug policy. The DEA administrator leads the department in enforcing the nation’s controlled substance laws and regulations, as well as investigating drug law violations at the interstate and international level. According to the DEA’s website, the role is currently being temporarily filled by Robert W. Patterson.

Undersecretary for Political Affairs

The U.S. State Department’s numerous vacancies include the undersecretary for political affairs, the department’s fourth-highest ranking official who manages daily decisions regarding regional and bilateral policy issues. The undersecretary also oversees the State Department’s bureaus of Africa, East Asia and the Pacific; Europe and Eurasia; the Near East; South and Central Asia; and the Western Hemisphere, as well as the Bureau of International Organizations.

Also still without a nominee in the State Department are the undersecretaries for civilian security, democracy and human rights; and economic growth, energy and environment. One level below, vacancies include assistant secretaries for political-military affairs; democracy, human rights and labor; and population, refugees and migration. The State Department is also lacking a number of ambassadors and representatives, including a representative to the European Union and ambassadors to Australia, Saudi Arabia, Turkey and South Korea, among other countries.

Though the undersecretary of political affairs position is temporarily being filled by Thomas A. Shannon, Jr., who first assumed the position under then-President Barack Obama in 2016, many of the other vacancies, including the other unfilled undersecretary positions, are currently vacant, according to the State Department’s website.

U.S. Secretary of State Rex Tillerson speaks during a media conference at the EU Council building in Brussels on Tuesday, Dec. 5, 2017. Virginia Mayo/AP

Undersecretary for Food Safety

The Department of Agriculture is currently going without an undersecretary for food safety. The position is responsible for overseeing the policies and programs of the Food Safety and Inspection Service and ensuring that commercial eggs, meat and dairy products are safe, properly labeled and packaged.

Director of the Census Bureau

As the country gears up for the 2020 Census — and potential changes floated by the administration could carry major consequences — the Department of Commerce is currently going without a head of the Census Bureau. The position is responsible for determining the bureau’s policies and overseeing the large-scale surveys and censuses it produces. Currently, those duties are being performed by Ron Jarmin, who is described on the Commerce Department’s website as “performing the nonexclusive functions and duties of the director of the Census Bureau.”

Commissioner of the Internal Revenue Service

Another important division currently without leadership is the Internal Revenue Service, whose unfilled commissioner role is responsible for presiding over the nation’s tax system and administering the tax code, as well as managing an agency with over 100,000 employees. The vacancy remains as we approach the 2017 tax return deadline and as the nation’s tax code prepares to undergo major reforms for 2018 under the Republicans’ recently-passed tax bill.

According to the Washington Post, the position’s duties are currently being filled by an assistant secretary of the treasury who reports to Treasury Secretary Steven Mnuchin. Jeff Hauser, the executive director of the Revolving Door Project, told the Post that filling the position in this way will make it harder for the IRS to function as an independent agency.

The Internal Revenue Service headquarters building in Washington, D.C., in April 2014. J. David Ake/AP

Principal deputy administrator of the National Nuclear Security Administration

The threat of nuclear war has become a concern under Trump’s presidency, and although the government is preparing to overhaul and expand their nuclear arsenal, they haven’t appointed someone to actually oversee it. The principal deputy administrator serves as the chief operating officer of the NNSA, which maintains and enhances the U.S.’s nuclear weapons, ensures the safety of nuclear propulsion plants for the U.S. Navy and “reduce[s] global danger from weapons of mass destruction,” according to the Partnership for Public Service.

The administrator position isn’t the only nuclear role still left unfilled in the Department of Energy. The deputy administrator for defense programs role at the NNSA is also still vacant, which is tasked with managing the Stockpile Stewardship Program that manufactures and maintains the nuclear arsenal and certifies their safety and reliability. Also still vacant is the deputy administrator for defense nuclear nonproliferation position, which works to detect weapons of mass destruction from other countries and prevent their proliferation, as well as reduce the risk of accidents in nuclear facilities worldwide.

Director of the National Park Service

The Trump administration has posed a threat to the country’s national parks and monuments — and continues to do so by not appointing someone to oversee them. The position, which manages and conserves over 400 park units covering 80 million acres across the country, is temporarily filled by Michael T. Reynolds, the deputy director of operations who is currently exercising the authority of the NPS director role.

Undersecretary for benefits at the Department of Veterans Affairs

Though Trump promised on the campaign trail to support veterans by overhauling the Department of Veterans Affairs, his administration has yet to even staff key roles in the department. The undersecretary for benefits role which oversees the Veterans Benefits Administration that provides pension funds, insurance, employment programs and other benefits to veterans is currently unfilled.

Also still vacant is the undersecretary for health role, which leads the Veterans Health Administration, the country’s largest integrated health care system.

The Veterans Affairs Department hospital in Denver in October 2017. David Zalubowski/AP

Director of the National Counterterrorism Center

The Trump administration’s anti-terrorism efforts are being hindered by its lack of an appointed director for the National Counterterrorism Center. The position, which is currently being filled by acting Director Russell Travers, is responsible for leading and integrating the U.S.’s counterterrorism efforts.

Another terrorism-related position currently without a nominee is the undersecretary for national protection and programs directorate at the Department of Homeland Security. The position is responsible for protecting the nation’s physical and cyber infrastructure from terrorist attacks, as well as from natural disasters and other catastrophes.

Director of the Office of Government Ethics

From Trump’s ties to his businesses to the potential collusion between the Trump campaign and Russia, the Trump administration has faced its share of ethical quandaries — yet the administration has yet to appoint someone to help Trump prevent them. The ethics head is responsible for leading the federal agency, which aims to prevent conflicts of interest in the executive branch. Currently, the position is being temporarily filled by David J. Apol, who serves as general counsel to the department as well as its acting director.

While there may be no Trump appointee yet presiding over the president’s ethics, past ethics officials have been quick to condemn the current commander in chief. The Citizens for Responsibility and Ethics in Washington, a watchdog group that includes Obama’s former ethics czar Norm Eisen and Richard Painter, the chief White House ethics lawyer for President George W. Bush, released a report declaring Trump’s presidency to be the “most unethical presidency” in modern times and potentially in the history of the country.