Immigrant visas allow an individual to legally gain access to a country for a variety of reasons. With the United States, an individual may obtain several different types of immigrant visas which pertain to their specific needs for traveling into the country. There are immigrant visas available for business or pleasure travel, medical treatment, employment, or even marriage. Immigration to the United States entitles a thorough background check and very specific information supplied about the specific period of time the individual plans to stay and what they plan to do while there. In some instances such as employment that have a longer term of stay associated with them, immigrant visas must be sponsored by an employer to ensure that there is in fact a work to keep the individual here for.