Forty-eight percent of U.S. dealers are using the Internet to purchase used vehicle inventory, up from 12% a year ago, according to a new study by Q2 Brand Intelligence.

The new study also reveals that dealers' experience with the Internet is largely positive, and that online purchasing will continue to grow.

For instance, 81% of dealers who purchased used vehicles online say they’ll do so again. Seventeen percent say they use the Internet to purchase at least 21% their used-vehicle inventory.

“Now that dealers are beginning to see the benefits the Internet affords in terms of cost and convenience, there's a big move in that direction," says Q2 Brand Intelligence Vice President David Bauer.

Increased challenges to acquiring used vehicles seem to be driving dealers online. For instance, 40% of dealers report that locating quality used inventory has become a greater challenge, up from 37% last year, says Q2, a brand research and business strategy firm.

The number of dealers listing "lack of time" as an impediment to replenishing such inventories increased from 10% to 17%. Conversely, issues surrounding used-vehicle pricing dropped slightly from 27% to 25%.

The survey also says:

* 92% of dealers report using the Internet at work, up 14 percentage points from 2000.

* 98% of dealers now have their own web site, up 4% from last year.