10 great companies for employees who love challenging work

Challenging yourself is a crucial part of long-term career success.

Harvard Business Review surveyed 260 CEOs and found that a majority had given themselves a relatively large challenge in the past two years. When researchers at Massachusetts General Hospital studied "superagers" — elderly people who function at extremely high levels academically, physically and professionally — they found that they challenged themselves mentally and physically more often than their peers.

Job site Monster partnered with employer review platform kununu to determine which companies gave employees the most challenging work.

Monster analyzed kununu's data from over 500,000 U.S. reviews, across 60,000 companies in 42 different industries. Employees from these companies were most likely to say that the work they were assigned was challenging:

Corporate headquarters: Northbrook, Illinois

What they do: "Allstate is the largest publicly held homeowners insurance company."

Number of jobs in 2017: 5,531

Frequently hiring for: Sales representatives, personal finance representatives, casualty adjusters

Why they're on the list: Allstate employes say that workers are "always pushed to do better and achieve realistic goals."

Corporate headquarters: Media, Pennsylvania

What they do: "Wawa operates convenience retail stores in six states plus the District of Columbia."

Number of jobs in 2017: 970

Frequently hiring for: customer service associates, night supervisors

Why they're on the list: Wawa's company's website says, "Wawa has a strong tradition of creating a culture of celebration and recognition, driven by the high priority we place on valuing our associates."

Corporate headquarters: San Antonio, Texas

What they do: "The United Services Automobile Association (USAA) is a diversified financial services group of companies that provides insurance to people and families that serve, or served, in the military."

Number of jobs in 2017: 2,907

Frequently hiring for: IT systems analysts, software developers, insurance adjusters, auditors

Why they're on the list: One employee said, "This is absolutely a challenging place to work at, but it is very rewarding, and what we do makes a difference."

Corporate headquarters: Batavia, Illinois

What they do: "Aldi is a discount grocery chain, with 24 divisions across the country, primarily located in the Eastern half of the U.S."

Number of jobs in 2017: 2,862

Frequently hiring for: Store associates, store managers, corporate buying, warehouse associates

Why they're on the list: "The job is very physical in nature and requires you to be able to multitask efficiently, but at the end of the day, [you] always feel proud of [your] work," says one Aldi employee.

Corporate headquarters: Atlanta

What they do: "Delta is the second largest U.S. airline."

Number of jobs in 2017: 1,984

Frequently hiring for: Reservation and ticket agents, marketing managers, customer service agents

Why they're on the list: One staff member explained that Delta employees find challenges exciting. "Being a flight attendant is challenging every day. You never know what to expect, but that is what makes it fun," they said.

Corporate headquarters: Mayfield, Ohio

What they do: "One of the largest auto insurers in the U.S., Progressive also insures homes, boats, motorcycles, and RVs."

Number of jobs in 2017: 1,803

Frequently hiring for: Claims adjusters, customer service representatives, lawyers, paralegals, insurance sales agents

Why they're on the list: "We had tough goals, but we were allowed to go about them however we needed to. We were able to cross-train and work with many, many other groups and people," says one former employee. "Deadlines were tough, and quality assurance goals were super high, but everyone gave it their all."

Corporate headquarters: Cincinnati, Ohio

What they do: "Procter & Gamble is a manufacturer of family, personal and household care products."

Number of jobs in 2017: 1,085

Frequently hiring for: Industrial engineers, sales managers, sales representatives, market research analysts

Why they're on the list: "The job is very physically and mentally challenging," says one P&G employee. Employees also said that challenge is what makes them "very proud" of the work they do.

Corporate headquarters: Washington, D.C.

What they do: "A branch of the United States military, the Army provides prompt, sustained land dominance."

Number of jobs in 2017: 64

Frequently hiring for: Registered nurses, computer user support specialists, psychologists, physicians

Why they're on the list: Service members said, "The Army is very challenging, but it is just as rewarding."

Corporate headquarters: Arlington, Virginia

What they do: "A branch of the United States military, the Marines are uniquely responsible for conducting air, ground and amphibious operations."

Number of jobs in 2017: 2,179

Frequently hiring for: Social service assistants, computer user support specialists, information security analysts

Why they're on the list: Marines pride themselves on being "held to higher standards." According to their website, the "determination to win, eagerness to fight and high standard of excellence are all traits strengthened in the Corps. "

Corporate headquarters: Richmond Heights, Ohio

What they do: "OMNI Systems is one of the largest, privately owned label converters in the U.S."

Number of jobs in 2017: 5

Frequently hiring for: Printing press operators, business development sales executives

Why they're on the list: Reviewers say, "All Omni employees are held to the highest standard of quality."

Topping the list as the company where employees most often say that the work is challenging is Omni Systems. Based out of Ohio, Omni System is a label converting company that is "building a high-performance culture through innovation and relentless pursuit of excellence."

Unsurprisingly, the United States Marine Corps and the United States Army came in second and third, respectively, on the list of companies with challenging work.The Marine Corps uses Challange Coins in order to congratulate hard work and honor.

Many different industries all landed spots on Monster's ranking. Consumer packaged goods companies like Proctor and Gamble, transportation companies like Delta and food retailers like Aldi all made the list.

Moritz Kothe, CEO of kununu adds, "It's fascinating to see which industries and companies are excelling in areas that are important to today's workers, and what areas employees feel need improvement. It's up to employers to take this feedback into consideration as they compete for talent in an ever-evolving marketplace."

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