Screening, in general, is the investigation of a great number of something (for instance, people) looking for those with a particular problem or feature. One example is at an airport, where many bags get x-rayed to try to detect any which may contain weapons or explosives. People are also screened going through a metal detector. Even though the procedure aims at a large number of screens, it is always equivalent to sampling in statistics, because the complete population is almost always unaccessible for screening.

Screening has other, more specific meanings:

• In physics, electric field screening refers to the dampening of an electric field by mobile charges
• Screening (economics)
• Screening (medicine)
• Screening for pharmacological activity during drug discovery
• part of the process of Environmental impact assessment.
• hampering an opponent's attempts at reconnaissance
• a type of tactic (sometimes legal, sometimes not) in sport games such as basketball or volleyball
• a screening can refer to the display of a film in a movie theatre or screening room