To apply for a NEXUS card, you need several original documents to prove your citizenship, identity, and residency. First, you must provide proof of citizenship, such as a valid passport, a birth certificate with a government-issued photo ID, or a citizenship certificate. If you are a permanent resident rather than a citizen, you’ll need your Permanent Resident Card (Green Card in the US). You also need proof of residency, which is typically a valid driver’s license or a provincial/state ID card with your current address; if those aren't available, utility bills or bank statements are often accepted. If you are working or studying in either the US or Canada, you must also provide your valid work or study permits. Since NEXUS is a "trusted traveler" program, these documents are used during a mandatory background check and in-person interview to verify you are low-risk.