Whether a person is a nonimmigrant coming to the U.S. for a temporary visit, is coming to study, is coming to work, or is coming in one of the other nonimmigrant categories, consular processing can play a major role in the status of the individual. Consular processing can also play an equally important role in the process for a person who is immigrating to the U.S. on a permanent basis.
Whether one is a nonimmigrant or an immigrant, there are a couple of ways to move from one status to another. One can either change or adjust status through U.S. Citizenship and Immigration Services if they are already in the U.S., or they can secure a visa and be admitted in the particular immigrant or nonimmigrant classification through consular processing.
Which particular process is used will depend on many different factors and you will need to carefully review those factors with your lawyer prior to choosing which route to follow. How your case progresses if consular processing is pursued will also differ based upon your country of nationality and the U.S. Consulate or Embassy you process through. Many of the U.S. Consulates and Embassies have their own particular way of processing cases. Research on the particular U.S. Consulate or Embassy will be necessary to ensure that all the particularities about the location are known prior to proceeding. These particularities include the manner in which forms are filed, communication with the U.S. Consulate or Embassy, the documents the consular official wants to see, the process of having the visa placed in the passport, etc.. In addition, the nationality of the applicant can also affect the process in that some countries require exit permission for their nationals before the national travels abroad to reside permanently. Failure to gain such permission can affect the U.S. visa process and can also possibly affect the status of the foreign national in their home country should they decide to return in the future.
As you can see, there are many factors involved in choosing the process and also many factors involved in the process itself.
Generally, if consular processing is chosen then a petition is filed and adjudicated by the Government. If the petition is filed in the U.S. then the case will be sent to the National Visa Center (NVC) upon approval. Depending on the type of case involved, the NVC may carry out a lot of the initial processing on the case prior to sending it on to the embassy or consulate for final interview and adjudication.
Some useful links to provide the prospective nonimmigrant or immigrant a glimpse into the process are: