O Visas

The alien must demonstrate extraordinary ability by sustained national or international acclaim and must be coming temporarily to the United States to continue work in the area of extraordinary ability.

To be classified under the O-1 nonimmigrant visa category, you must have extraordinary ability in the sciences, arts, education, business, or athletics or a demonstrated record of extraordinary achievement in the motion picture or television industry.
Extraordinary ability means a level of expertise indicating that the person is one of the small percentages who has risen to the very top of the field of endeavor.

Extraordinary ability in the field of arts means distinction.  Distinction means a high level of achievement in the field of the arts such that the alien is considered renowned, leading, or well-known in the field of arts. The arts include, but are not limited to, fine, visual, culinary and performing arts.  Therefore, if you are a distinguished pianist, violinist, ballet dancer, conductor, chef, graphic designer, etc. then O-1 might be an option for you. Essential personnel such as directors, choreographers, set designers, make-up artists, and stage technicians are also included in this category.
To qualify as an alien of extraordinary ability in the field of arts, the alien must be recognized as being prominent in his or her field of endeavor as demonstrated by the following:
Evidence that the alien has been nominated for, or has been the recipient of significant national or international awards or prizes in the particular field such as an Academy Award, an Emmy, a Grammy, or a Director’s Guild Award; OR
At least three of the following forms of documentationEvidence that the alien has performed, and will perform services as a lead or starring participant in productions or events which have a distinguished reputation 
Evidence that the alien has achieved national or international recognition for achievements evidenced by critical reviews or other published materials by or about the individual in major newspapers, trade journals, magazines, or other publications;
Evidence that the alien has performed, and will perform, in a lead, starring, or critical role for organizations and establishments that have a distinguished reputation
Evidence that the alien has a record of major commercial or critically acclaimed successes as evidenced by such indicators as title, rating, standing in the field, box office receipts, motion pictures or television ratings, and other occupational achievements reported in trade journals, major newspapers, or other publications;
Evidence that the alien has received significant recognition for achievements from organizations, critics, government agencies, or other recognized experts in the field in which the alien is engaged. Such testimonials must be in a form which clearly indicates the author’s authority, expertise, and knowledge of the alien’s achievements; or
Evidence that the alien has either commanded a high salary or will command a high salary or other substantial remuneration for services in relation to others in the field, as evidenced by contracts or other reliable evidence

Yes! Those in the film and television industry are held to a higher standard than those in the arts although the same criteria are used.
To qualify for an O-1 visa in the motion picture or television industry, the beneficiary must demonstrate a history of extraordinary achievement such that the alien is recognized as outstanding, notable or leading in the motion picture and/or television field. The applicant must meet the level of extraordinary achievement, and not just mere distinction.
If you are a distinguished movie producer, film director, production designer, actor/actress, cinematographer, etc. then O-1 might be an option for you.

Applicants in these areas must show that they are one of a small percentage to have reached the top of their field. They can show national or international acclaim through receipt of a major international award OR show evidence that they meet three of the following criteria:
Has received a nationally or internationally recognized award;
Holds membership in an organization that requires outstanding achievement;
Published materials about applicant in professional or trade publications;
Has served as a judge of the work of others;
Has produced original scientific or scholarly work of major significance in their field;
Is the author of scholarly work;
Has been employed in a critical role by an entity with a distinguished reputation;
Has received or will receive a high salary.

Yes, you do need an employer to sponsor you in order to file for an O petition.  However, if you are an alien and own a production company in Hollywood, for example, you can utilize that production company to petition O-1 for you.

Any U.S. employer, a U.S. agent, or a foreign employer through a U.S. agent can petition for you. However, the petitioner must at least be in the artist’s field of expertise. This also means, that a U.S. citizen, who is in the artist’s field may petition for them as long as there is a legitimate reason why the petitioner requires the artist to work in the United States.

O visas will be granted for the time period that is required for that event but not longer than 3 years.

Yes, if the O-1 will be expiring soon, you can file for O-1 extension in 1 year increments. Alternatively, you may apply for a new three year visa.

Yes, there are 3 main types of O visas:
O-1 classification: Alien with Extraordinary Ability in Science, Arts, Education, Business or Athletics
O-2 classification: Alien accompanying and Assisting in the Artistic or Athletic Performance by O1
O-3 classification: Spouse or Child of O-1 or O-2.

Yes.  As a support staff of a famous artist, you can qualify for O-2 visa.
O-2 visas are available for those accompanying the principal O-1 visa holder if their work is an integral part of the principal visa holder’s performance or artistic endeavors and they possess critical skills and experience that are not of a general nature and cannot be performed by other individuals.