The US government is finally keeping it REAL

After two decades in the making, the US government’s REAL ID Act takes effect today, with major implications for travelers flying within the country.

Moving forward, people aged 18+ will need to present REAL ID-compliant forms of identification when boarding US domestic flights at airports, visiting certain government buildings like federal courthouses, or entering nuclear power plants (everyone’s favorite pastime).

What is a REAL ID? Acceptable forms include state-issued IDs or driver’s licenses that are marked with a star in the upper right corner, US or foreign passports, and permanent resident cards.

• The new rules are part of a larger federal law aimed at setting “minimum security standards” for identification materials, which was initially approved by Congress in 2005 but experienced several delays.

Overall, the TSA says 81% of travelers at its checkpoints currently present a Real ID-compliant form of identification.

And if keeping it real goes wrong…Travelers in the US who don’t own a form of REAL ID will still be able to fly domestically—for now—but should be prepared for extra scrutiny and wait times, Homeland Secretary Kristi Noem said Tuesday.