Some UAE visa applications require a Police Clearance Certificate (sometimes called a Certificate of Good Conduct) from the applicant's home country or country of prior residence — a requirement that catches applicants off guard when it applies, since it is not needed for every visa type or nationality.
What a Police Clearance Certificate actually is
It is an official document, issued by a police or judicial authority in the country where you have lived, confirming whether you have a criminal record. For UAE purposes, it typically also needs to be attested — following a similar authentication chain to other official documents covered elsewhere in this site's content — before it is accepted.
When this requirement applies
This is more commonly required for longer-term residence visa categories and certain employment sectors than for short tourist or visit visas, though specific requirements can vary by nationality, sponsor, and visa category. Confirm directly with your employer, sponsor, or the relevant UAE authority whether your specific application requires one, since assuming it does not apply can cause a significant delay if it turns out to be required.
How long it takes to obtain
Processing time varies considerably by home country — some issue certificates within days, others take weeks — so if you know your visa category typically requires one, request it well before you need to submit your UAE visa application, since the attestation step that typically follows adds further time on top of the certificate's own processing.