I got harnesses that clip to the seatbelts. They wonít protect in a serious crash, but they keep them from flying around if I stop suddenly. I used Kurgo brand. I attach a traffic lead to the closed seat belt then clip it to the harness. Dogs can still slip around or twist the harnesses if they are very agile but itís better than nothing. I also have a Sleepypod Clickit which is crash tested and approved, but I canít figure out how to make it work with my seatbelts. If anyone else uses one, I would like to see how you attach yours.