the only windows that roll down are the drivers and passanger seats, the back windows just flip out a crack. how much I roll the window down depends on which dogs are with me. Perky could not care less about windows, Blair is crated in the van just because he cant cope without his crate, he gets panicked and nervous if his kennel is not there for him to hide in. Happy sticks her head out the window, I dont worry about her jumping out because well..its Happy, she is not the jumping sort unless she REALLY wants to come someplace with me. Misty I only roll the window down enugh for her to stick her nose out, and same for Ripley.