A great concern with airline deregulation, particularly in the wake of the tremendously popular budget airlines, is the mistreatment of passengers. Nightmare stories of passengers trapped in planes on runways for several hours or even overnight lead many to believe that some government regulation is required to protect passenger rights onboard flights. Since government interest often extends only so far as to enforce airplane safety, passengers are usually left with no legal recourse to sue an airline for mistreatment. As of the 21st century, passenger bill-of-rights have become a hot topic in regards to the industry.