Others, such as students who are already living temporarily in the United States, may apply for permission to work under the terms of their immigration classification or change to another classification. In all cases, permission to work must be received before starting to work. As a general rule, an alien living outside the United States who wishes to work temporarily in the U.S., must first get a job offer from a U.S. employer. It is the employer who starts the paperwork. Following INS approval, processing is transferred to a U.S. Embassy or Consulate abroad.
Entry is permitted for a limited period based on the premise that the job is of a temporary nature.
Most classifications permit renewals to not more than six years. There are a number of classifications which permit employment and each has its own criteria and a process which must be strictly adhered to. Some, such as student classifications, may permit employment in connection with the student's studies. Depending on the classification, the conditions may involve a determination that a U.S. worker is not being displaced and workers are in short supply in the location concerned. In all cases, it is expected that the alien is qualified and not paid below the local going rate.