Jeff Sorenson, second from left, head of A.T. Kearney’s public sector and defense business, with employees Hamaad Chippa, left, Genevieve Neilsen and Steve Hunt, at the company’s office in Rosslyn. (Jeffrey MacMillan/For the Washington Post)

When Jeff Sorenson left the military in late 2010, the three-star general had no idea what he would do.

He thought about entering banking — but was quickly disillusioned by a contact who told Sorenson he was too old. Consulting wasn’t high on the list; the former Army chief information officer said he had not had good experiences with some of the well-known firms.

But when an executive at consulting company A.T. Kearney asked him to lunch, he figured it was worth the free meal. Several months later, he joined the company, and this summer took over the unit’s Rosslyn-based public sector and defense business.

Like many in the Pentagon, Sorenson had never heard of A.T. Kearney before the company’s phone call. Indeed, the commercially focused consulting firm only started working with the government about a decade ago and formalized a public sector group in 2007.

But Sorenson is now seeking to grow the company’s business and profile. A.T. Kearney attracted attention earlier this year after undertaking a study for the Army on the state of the companies and suppliers building combat vehicles.

The company may also benefit from its approach. A.T. Kearney only operates under fixed-price contracts for limited projects, rather than seeking open-ended engagements where the amount of work can be fickle. Sorenson described the company’s employees as the “special forces” of consulting.

The global parent company, based in Chicago, has about 3,000 consultants across close to 60 offices. It was originally the Chicago office of well-known consulting firm McKinsey & Co., and was run by Andrew Thomas Kearney, who had joined McKinsey in 1929. The company was renamed in the 1940s after Kearney split that office from McKinsey.

In 1995, A.T. Kearney was acquired by IT company EDS (which has since been bought by Hewlett-Packard), and in 2006, A.T. Kearney partners purchased the firm back.

Now, the public sector and defense group is made up of about 56 consultants, Sorenson said.

Company executives said their biggest competition is in “single-shingle” shops, typically military or industry experts running their own consulting businesses.

But perhaps the bigger challenge, they said, can be getting on so-called contract vehicles. Contract vehicles, which have become the government’s preferred way to buy services, are set up to allow agencies to make repeated purchases from a culled group of vendors without going through a separate procurement process for each piece of work.

“In many cases, [winning a place on a contract vehicle] is a issue in terms of trying to get on contract,” Sorenson said.

Company executives said they’re seeing opportunity in the Defense Department’s push for improved acquisition techniques as spending declines.

“To some degree, the cost pressures are really a good thing for us,” said Randy Garber, a partner in the public sector. “Perpetuating the status quo is not going to cut it for [the government] anymore.”

And Sorenson said he’s in a position to draw on his experiences in the military.

“Having been where I was, I kind of knew where some of the problem sets were,” he said. “I don’t want to say I know where all the skeletons are ... [but] I still kind of know those people.”