The upcoming Sundance Film Festival in Utah, which will feature 189 feature films, documentaries and animations, is a chance to reflect on a vital, but often ignored, spoke in the immigration wheel.

Two visa categories, the O and the P visa, usually forgotten in the slew of Hs and Ls, are brought to the forefront during events like Sundance.

The O-1 visa category is for individuals with an extraordinary ability in the sciences, arts, education, business, or athletics. Usually those eligible have attained excellence of the order of an Olympic medal or a Grammy Award.

However, in the absence of such a glittering accolade, the applicant can still qualify for the visa status by showing sustained national or international excellence. Assistants of these individuals are usually eligible for an O-2 visa.

The P-1 visas don’t require such outstanding levels of achievement and are for entertainment groups, athletes and artists participating in cultural exchange programs. Applicants must be able to substantially prove that their achievements are renowned, leading or well-known in more than one country.

P-2 visas are reserved for artists and entertainers who perform individually or as part of a group but they must agree to a reciprocal exchange program that provides for the temporary exchange of artists and entertainers. Coaches of P-1 and P-2 applicants are usually eligible for P-3 visas.

It’s important to remember that O and P petitions may only be filed by a U.S. employer, a U.S. agent, or a foreign employer through a U.S. agent.