A more thorough explanation:

Labor certification

Labor certification is a process that employers must go through before they can apply for a visa for non-U.S. citizens they wish to employ in the United States. The process involves attempting to hire U.S. employees first and only if unsuccessful, applying for a labor certification for a foreign applicant. If a job does not qualify for an exception, a foreign employee must receive a labor certification to work long-term in the United States. To receive a labor certification, the employer must establish a legitimate job posting with accurate details and experience requirements. The employer must also receive a prevailing wage determination that sets a minimum compensation for the job posting. The employer then must follow guidelines for posting the job for at least 30 days in different locations. Only if no qualified applications are submitted may the employer file for a labor certification for a foreign applicant. If the Department of Labor suspects that the employer is not being honest in the process, the PERM application may be rejected or audited.

Example 1: A company wants to hire a software engineer from India to work in their U.S. office. The company must first attempt to hire a U.S. software engineer for the job. If no qualified U.S. applicants apply, the company can then apply for a labor certification for the Indian software engineer.

Example 2: A restaurant wants to hire a chef from France to work in their U.S. restaurant. The restaurant must first attempt to hire a U.S. chef for the job. If no qualified U.S. applicants apply, the restaurant can then apply for a labor certification for the French chef.

These examples illustrate the process of labor certification. Employers must first attempt to hire U.S. employees before applying for a labor certification for a foreign applicant. This ensures that U.S. citizens have the opportunity to apply for the job before it is offered to a foreign employee. The process also involves establishing a legitimate job posting with accurate details and experience requirements, receiving a prevailing wage determination, and following guidelines for posting the job for at least 30 days in different locations. Only if no qualified U.S. applicants apply may the employer file for a labor certification for a foreign applicant.