A strip search is a practice of searching a person for weapons or other contraband suspected of being hidden on their body or inside their clothing, and not found by performing a frisk search, but by requiring the person to remove some or all clothing. The search may involve an official performing an intimate person search and inspecting their personal effects and body cavities (mouth, vagina, rectum, etc.). A strip search is more intrusive than a frisk and requires legal authority. Regulations covering strip searches vary considerably and may be mandatory in some situations or discretionary in others.

A strip search of a suspect of a recent violent crime may additionally be useful for finding blood of the victim, signs of a fight, etc.

In North America, civil lawsuits, as well as criminal code charges against strip searches have usually been successful when a person is strip searched by someone of the opposite sex, especially in cases where a woman has been strip searched by a male guard or guards. The more disputed legal cases have often involved the presence of people of the other gender during a strip search. Some of these cases have been less successful because of the legal technicality of who was actually performing the strip search, i.e. if more than one guard is present, the search is often (legally) said to be performed by the person or people giving the orders or instructions to the person or people being searched.

Another legal issue is that of blanket strip searches, such as in jails where detainees are routinely strip searched prior to conviction of a crime. Courts have often held that blanket strip searches are acceptable only for convicted persons. For detainees pending trial, there must be a reasonable suspicion that the detainee is in possession of weapons or other contraband before a strip search can be conducted. The same often holds true for other situations such as airport security personnel and customs officers, but the dispute often hinges on what constitutes reasonable suspicion.

In order to bypass the legal reasonable suspicion requirement, and because strip searches can be humiliating, the search is often made less overt, as part of an intake process, that includes a mandatory shower. For example, most prisons also include a mandatory shower along with a change of clothes. The shower serves to make the strip search less blatant as well as providing the additional benefit of removing contamination (in addition to removing weapons or other contraband). Many shelters require new arrivals to hand over all their clothing for a wash, as well as requiring them to have a shower. These rules also enable a discreet check for weapons or other contraband, with less legal implications, being less objectionable because the requirement is applied to everyone entering a facility. It is less offensive to clients than requiring them to undergo an overt strip search.

Security procedures at facilities that mine and process gold, silver, copper, and other high-value minerals may constitute an incidental strip search. At the end of the workday, miners must remove all work clothes before entering a shower facility and then exit nude through a metal detector to a separate changing room where street clothes are stored.

The courts have often held that requiring a person to have a shower as a condition of entry into a space (such as a prison, shelter, or the like) does not, in itself, constitute a strip search, even if the shower and surrounding space are so constructed as to afford visibility of the unclothed body by guards during the showering process.^{[citation needed]}

Hospitals often also have a mandatory shower, during lockdown, when mass decontamination is called for. Paul Rega, M.D., FACEP has specifically identified mass decontamination as providing the added benefit of checking for weapons or other contraband, as well as searching for clues among the clothes of persons found at a terrorist attack crime scene where it is recognized that the perpetrator(s) could be among the persons detained for decontamination.