Abstract: A pet containment assembly for containing pets within a closed automobile while allowing air to circulate freely through the windows of the automobile to provide a safe and comfortable environment for the pets, the assembly having a two-piece adjustable frame which has both stationary horizontal bars and telescoping horizontal bars so that the frame can be extended to the full width of a window opening in the automobile, the frame being held in place in the opening by tabs on the frame which fit into the grove of the window opening and a groove in the frame into which the top edge of the window fits, thereby securing the frame in the opening.