As you can tell from my avatar, my dog Hoover likes to ride in the Caddy, but since he's a lab, he's not exactly a lap dog. Occasionally, he'll try to climb up front, but I make him stay in the back seat.
When I first adopted him, I tried to use a dog seat belt harness, but Hoover got all tangled up in it and managed to chew almost completely through the seat belt (different car) in a 15-minute drive.
When I was changing out the fuel injectors Sunday, I put Hoover on a tie-down in my front yard, and twice he managed to climb into the car through the open driver's door window. He REALLY wanted to go for a ride.