US immigration regulations provide that the petition for a professional classification must be accompanied by evidence that the alien holds a baccalaureate degree or a foreign equivalent degree, and by evidence, the alien is a member of the professions.
Evidence of a baccalaureate degree shall be in the form of an official college or university record. To show that the alien is a member of the professions, the petitioner must submit evidence showing that the minimum of a baccalaureate degree is required for the occupation.
For classification as a skilled worker, the USA immigration laws provide that skilled worker means an alien who is capable at the time of the petitioning of performing skilled labour requiring at least two years training or experience not of a temporary or seasonal nature. Relevant post-secondary education may be considered relevant for this purpose.
The USCIS requires that the alien possesses two years of training, work experience and college education, not just capability to perform the job. College education or work experience must be verified by certificates or letters.
These workers are categorized as unskilled and those who meet the education and work experience for the job. The petitions are for those positions requiring less than two years of training, work experience or college education.
There is a definite advantage in being classified as a skilled worker as opposed to an unskilled worker. As an unskilled worker, the alien could be waiting several more years for a green card petition or visa application to be approved.
For all the above classifications, the employment must be offered as a result of a lack of qualified US workers willing and able to perform the job in question and furthermore, the job classification does not adversely affect US workers.