I Am an Employer: How Do I… Hire a Foreign National for Short-Term Employment in the United States? [open pdf - 1MB]
"This customer guide covers a complex area of U.S. law and Government regulations. If in doubt, employers may wish to consult specialists in this area to ensure they proceed correctly. Employers sometimes need to hire foreign labor when there is a shortage of available U.S. workers to fill certain jobs. Under certain conditions, U.S. immigration law may allow a U.S. employer to file a Form I-129, Petition for a Nonimmigrant Worker, with U.S. Citizenship and Immigration Services (USCIS) on behalf of a prospective foreign national employee. Upon approval of the petition, the prospective employee may apply for admission to the United States, or for a change of nonimmigrant status while in the United States, to temporarily work or to receive training. For most employment-based nonimmigrant visa categories, the employer starts the process by filing Form I-129 with USCIS. Form I-129 is available on our website at www.uscis.gov. Please note that in some cases the employer must file a Labor Condition Application or Application for Alien Employment Certification with the Department of Labor (DOL) and/or obtain certain consultation reports from labor organizations before filing a petition with USCIS. There are numerous nonimmigrant, employment-based visa categories. Under all of these categories, listed below, the foreign national must meet specific requirements for the occupation covered in the petition."
U.S. Citizenship and Immigration Services: http://www.uscis.gov/