An O-1 petition can include only one alien of extraordinary ability in the arts entering the U.S. to work in his/her area of expertise. "Extraordinary ability" for purposes of the arts is not an especially high standard. It means "distinction" which, in turn, means a high level of achievement in the field, substantially above that ordinarily encountered. With a well-crafted petition, seasoned or accomplished artists, those who have achieved sudden success, and even students and child prodigies who function at a level appropriate to O-1 status should qualify. Although U.S. Citizenship and Immigration Services (USCIS) service centers vary in their interpretation of the extraordinary ability standard as applied to performing artists, nonetheless, if a USCIS service center questions whether the alien meets the standard of distinction, the petitioner first should look closely at how much effort went into the petition in the first place.