This visa is essentially another category of employment-based residency. It is distinguished by the key requirement that applicants are highly accomplished in their field (the arts, sciences, education, business, and sports). This is therefore considered by the USCIS as a "first preference" visa, the category of highest priority. EB-1 visas are a pathway to getting a green card.
If you have "extraordinary ability" (EB-1A), you can petition for yourself. If you are an "outstanding professor or researcher" (EB-1B), your US-based employer must file the form, and if you are "multinational manager or executive" (EB-1C), your employer must likewise file the paperwork for you.
The following are the requirements for each class of EB-1 visas:
You have demonstrable extraordinary ability in the sciences, arts, education, business, or athletics through sustained national or international acclaim. Your achievements must be recognized in your field through extensive documentation. Note: you do not require an offer of employment to apply for this visa.
You have achieved international recognition for your outstanding achievements in a particular academic field. You must have at least 3 years experience in teaching or research in that academic area. You must be entering the United States in order to pursue tenure or tenure track teaching or comparable research position at a university or other institution of higher education. You must include specific documentation required by the USCIS and an offer of employment from your prospective US employer.
You must have been employed outside the United States in the 3 years preceding the petition for at least 1 year by a firm or corporation and you must be seeking to enter the United States to continue service to that firm or organization. Your employment must have been outside the United States in a managerial or executive capacity and with the same employer, an affiliate, or a subsidiary of the employer.
The USCIS lists several ways by which you need to demonstrate your abilities within each category. For example, EB-1A applicants can show that they have won a Nobel Prize in their field, or an Olympic medal. It's important that you meet these strict requirements for each category.
The USCIS' decision-making on EB-1 visas is nuanced, even as its guidelines are clear. Your application would need to effectively convey your highly unique and special skill set. A skilled and experienced immigration attorney can ensure that you convey your abilities in your application to the fullest.
TThe above information was adapted from the www.USCIS.gov website and is current as of January, 2018.