In the world of business travel, the adage that time is money rings true.

Websites such as Expedia, Kayak and Priceline—online aggregators of hotel and airfare rates—have made it possible for business travelers to plan and book business trips at the press of a computer key. Travel agencies, by comparison, may seem an arcane service. Why pay a travel agent a commission to find the lowest hotel room price when you can do it yourself in a matter of seconds?

But travel websites have not proven to be the disruptive force they once threatened to be. While some businesses exclusively use do-it-yourself websites, travel agents say that business is growing.

"The need for a travel agent is becoming stronger," says travel author Chris McGinnis.

McGinnis began his career as management consultant at Chicago-based consulting firm Alexander Proudfoot, a job that required weekly international travel. He eventually left to establish Travel Skills Group, a company that consulted professionals on how to optimize their business trips.

"Most business travelers are savvy enough to know that there’s not one single best website…in order to get the best deal you do have to shop around." And that takes time, which many traveling businesspeople don’t have.

Allowing travelers to focus on their work rather than the logistics of a business trip has been a major factor in the recent growth in the travel agent industry.

"The impact of the various Internet sites was felt years ago. Actually, in 2011, we’ve seen more business come back," says Patrik Olson, a travel consultant at Studio City, California-based Willet Travel who has worked in the travel agency industry for more than 16 years.

From 2010 to now, 73 percent of airline tickets in the U.S. were sold through agencies, he says.

He attributes this rise to travelers' lacking the time to handle the work that goes into planning complicated travel.

"They don’t have time to be Kayak-ing and then submitting their own receipts for reimbursement and what not," he says. "We do all of that for them."

And what many travelers don’t realize is that travel agencies frequently offer rates lower than those found anywhere online, Olson says. Despite promising the cheapest prices available, hotel and airfare websites are usually unable to match the privately negotiated rates exclusively offered to consultants like Olson.

Some of the world's busiest business travelers still don't view travel agents as a necessary resource, however.

"I do all my own booking," boasts Thomas Stuker, an independent car sales consultant from Illinois that travels to dealerships throughout the U.S. and Europe.

Business travel is a lifestyle for Stuker. Over the summer, he flew his 10 millionth mile with United Airlines, a feat that garnered him international headlines and comparisons to George Clooney's character in the film "Up in the Air."

Fittingly, he was five minutes from takeoff on a plane in Los Angeles when he first spoke to Inc. Two and a half hours later in Dallas, he talked about the importance of businesspeople handling their own traveling accommodations.

"I recommend that someone who plans on traveling a lot, to learn to travel," he says.

For Stuker, handling his own travel has resulted in an excellent personal and professional relationship with United Airlines and numerous perks.

"I know every agent on a first name basis. They know me. They go out of their way to give me extraordinary service. They’re like family," he says.

Few, if any, businesspeople travel as much Stuker, though.

But even companies with employees who travel less frequently have found effective ways to plan their employees' travel without utilizing travel agencies.

TerraCycle, a Trenton, New Jersey-based waste management consulting firm, has 105 employees, 20 of whom travel. Of those 20, five are "highly intense" travelers, says TerraCycle CEO Tom Szaky.

Some of Szaky’s traveling workers use websites like Kayak and Orbitz, but many turn to a few select employees within the company to handle elaborate arrangements. These employees have proven to be standouts when it comes to managing complex flying, and now act as de facto, in-house travel agents.

One such employee is TerraCylce chief administrative officer Ricahrd Perl, the second most frequent traveler at the company. He has flown between 50,000 and 100,000 miles a year for the past 25 years.

"I usually do better than travel agents," Perl reveals regarding his ability to book cheap flights.

The main advantage to handling his and fellow employees' travel is that he has an intimate understanding of each person's travel preferences and busy schedule. There is no added value in using a travel agent, he says.

Despite business travelers who insist on self-reliance, travel agencies have managed to not only remain relevant, but expand business.

"Businesspeople are way too devoted to their specialty to be bothered with travel," McGinnis says.

And for people like McGinnis, travel is their specialty.