A new study from the Global Business Travel Association Foundation, the organization's education and research branch, reveals that rental cars remain the most popular method of ground transportation among today's business travelers.

The GBTA Foundation's 2015 Ground Transportation Study shows that 36 percent of road warriors rely on rental vehicles during their business trips, while 24 percent utilize taxis.

Meanwhile, 13 percent rely on chauffeured transportation and 11 percent use ride-sharing services such as Uber and Lyft.

Beyond the most commonly used methods, the study found that traveler and vehicle safety, timely pick-up and convenient payments methods are among the most important factors often considered when choosing a form of ground transportation. 

The GBTA Foundation's research shows that three in four business travelers and eight in 10 travel buyers consider those factors to be among the most important. But still, the study found that less than one-quarter of travel buyers are "very familiar" with duty of care aspects affecting each aforementioned method of ground transportation. 

And only one-third of business travelers said they were "at least somewhat familiar" with those duty of care aspects. 

"Our research shows one in four (24 percent) travel buyers say their company does not allow their business travelers to use ride-sharing companies, by far the highest percentage for any form of ground transportation," said GBTA executive director and COO Michael McCormick in a statement. "In addition, a large number of companies still have not adopted policies around ride-sharing companies, revealing a need for education about the benefits and the risks."

McCormick added that the "GBTA hopes this study is the start to closing that knowledge gap."

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