car rides with a dog

[LostAndConfused]

How do you guys secure your dog when you're driving?

For puppy class, since both of us go, one drives and the other holds Hudson. On the long drive to Ohio and back, we used a wire crate. I don't think the crate will fit him much longer and the larger crate isn't going to fit into our little cars. I've looked at the harnesses, but I think the puppy is too wiggly and I've looked at the hammock type...things. I like that idea because it gives him room, but it doesn't secure him in anyway.

So, what do you guys do?