Per the application process outlined on their career site, Heathrow Airport requires a very thorough background check process that includes five years of employment history, the right to work in the U.S., and a criminal background check. Due to industry regulations, certain jobs may require more detailed checks like counter-terrorism checks, drug testing, and occupational medical exams. Knowing that this is a critical part of the employment process following an accepted offer, your interviewer needs to be assured that you will consent to and pass all required checks. This is a time to be honest with your interviewer and disclose anything that may arise in a background check, including any criminal offenses you may have or gaps in employment.