Deterrence in relation to criminal offending is the idea or theory that the threat of punishment will deter people from committing crime and reduce the probability and/or level of offending in society. It is one of five objectives that punishment is thought to achieve; the other four objectives are denunciation, incapacitation (for the protection of society), retribution and rehabilitation.

Criminal deterrence theory has two possible applications: the first is that punishments imposed on individual offenders will deter or prevent that particular offender from committing further crimes; the second is that public knowledge that certain offences will be punished has a generalised deterrent effect which prevents others from committing crimes.

Two different aspects of punishment may have an impact on deterrence, the first being the certainty of punishment, by increasing the likelihood of apprehension and punishment, this may have a deterrent effect. The second relates to the severity of punishment; how severe the punishment is for a particular crime may influence behavior if the potential offender concludes that the punishment is so severe, it is not worth the risk of getting caught.

An underlying principle of deterrence is that it is utilitarian or forward-looking. As with rehabilitation, it is designed to change behaviour in the future rather than simply provide retribution or punishment for current or past behaviour.