In general aliens who do not fit into family based immigration categories require labor certification (LC) to be able to immigrate to the U.S. A labor certification is an approval by the Department of Labor (DOL) for an offer of employment in the U.S. to a named alien.

The alien may be either physically in the U.S. at the time or in another country. Once the employer has received an approved labor certification from the DOL then the Alien may then file an immigrant petition with the U.S. Immigration and Naturalization Service (USINS). The immigrant petition leads to permanent resident status for the alien.