A park visitor participating in a guided hike into the Painted Desert in mid-July started experiencing heat-related medical problems. The temperature at the time was in the mid-90s and humidity was higher than normal. Interpretive rangers and staff of Petrified Forest Museum Association provided immediate care, then helped responding rangers with a carryout from the floor of the Painted Desert to the trailhead, where an ambulance was waiting. The victim’s condition eventually improved after being removed from the direct sun and receiving active cooling. One of the initial responders passed out and was injured after running from the floor of the Painted Desert to the trailhead. She was transported by ambulance to the nearest hospital, where she was treated for facial lacerations and broken teeth and released. An after-action review with the rescuers resulted in several excellent ideas for improvements in dealing with future similar incidents.