The U.S. National Security Agency’s mission is to collect, decode, translate and analyze the encrypted messages sent by foreign adversaries about military plans or terrorist plots and to prevent adversaries from hacking into U.S. defense systems.

The work day of one NSA worker may dramatically differ from that of another, says Catherine Aucella, the agency’s executive director.

“Some of them are sitting at a desk, doing really deep thinking and deep analysis on really hard problems,” Aucella says. Other NSA staffers travel throughout the world, doing hands-on projects, she adds. “The beauty of working at NSA is that, once you get in and you start to learn what the opportunities are, you can take your career in a lot of different directions.”

The agency hires computer scientists, data scientists, mathematicians and others with technical degrees, but it also values security-related credentials in the humanities or social sciences.

While someone with a computing or engineering degree might qualify for an NSA job as a network vulnerability analyst or defense analyst, an NSA employee with a math degree might be involved in figuring out an adversary’s complex secret code or developing encryption methods for U.S. military communications.

The science of making and breaking codes is commonly known as cryptology, and NSA employs many people who have studied this field.

NSA staffers with degrees in linguistics or foreign languages could help interpret and translate messages, and those with a degree in political science or international relations might provide strategic recommendations to U.S. leaders based on analysis of intelligence information.

“NSA is a big place, and we have a really diverse mission,” Aucella says, “so we actually need people at all levels of education and a variety of backgrounds – everything from high school students all the way up to people with Ph.Ds.”

All NSA jobs require U.S. citizenship and a security clearance. NSA job candidates should not have recently or frequently used illegal drugs, should be able to demonstrate good personal conduct overall and may need to undergo a medical screening.

High school, college and graduate students who are interested in working for NSA can participate in one of the agency’s many student programs, which include co-ops, fellowships, internships and scholarships. These programs are designed to introduce potential NSA employees to the agency, so they can decide whether it would be a good fit and develop skills helpful for their future careers.

NSA employees can take advantage of various career development opportunities while working. For example, NSA runs a National Cryptologic School that provides advanced education in cryptology and other subjects. There is also a general intelligence school run by the federal government that NSA workers can attend: the National Intelligence University.

Because NSA is part of the U.S. Department of Defense, one of its core goals is to shield U.S. weapons systems from foreign hackers.

Amyn Gilani, chief growth officer at the CounterCraft threat intelligence software company and a former NSA intelligence analyst, started working for NSA when he was a teenager, shortly after enlisting in the U.S. Air Force.

“It’s really hard to have more exciting careers after that,” he says. “You’ve peaked in your career at your first duty station.”

According to Gilani, who earned a bachelor’s degree in Middle Eastern history at the University of Maryland—College Park while working at the agency, NSA is a fast-paced work environment. “The whole conception about the government being slow and a big bureaucracy – it’s not always like that, especially not in NSA,” he says.

Working at NSA was exciting and meaningful, Gilani says. “It wasn’t just working behind a desk; we were a part of real missions that I can’t really talk about right now.”

Like many intelligence agencies, NSA requires its staffers to be discreet and not disclose sensitive details about projects to outsiders.

“Certainly, we’re not going to have a lot of current analysts appearing on CNN, talking about the work that they do,” Aucella says. “That’s not what we do. We do have a very robust internal recognition process within the agency.”

According to Aucella, roughly half of NSA employees have some kind of military affiliation while the others are civilians. “Our agency in particular really has a big emphasis on problem-solving and innovation and finding new ways to attack problems, so we find the best way to do that is to have that diverse body of employees that come together and think about things from a variety of different angles,” she says.

“Certainly, a strong sense of duty – dedication to mission – is something that’s kind of palpable at our agency,” Aucella adds. “They’re here if they want to make a difference, and that’s what keeps people here.”

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