The G nonimmigrant visa category is reserved for individuals coming to the United States for a temporary period who are representatives of international organizations.
Generally, this type of nonimmigrant visa is found among foreign national workers who serve the myriad of specialized agencies affiliated with the United Nations. G nonimmigrant visas may be granted to individuals who are:
(i) a designated principal resident representative of a foreign government recognized de jure by the United States, which foreign government is a member of an international organization entitled to enjoy the privileges, exemptions, and immunities as an international organization under the International Organizations Immunities Act 22 U.S.C. 288, note, accredited resident members of the staff of such representatives, and the members of his or their immediate family;
(ii) an other accredited representative of such a foreign government to such international organizations, and the members of their immediate family;
(iii) an alien able to qualify under (i) or (ii) above except for the fact that the government of which such alien is an accredited representative is not recognized de jure by the United States, or that the government of which he is an accredited representative is not a member of such international organization, and the members of his immediate family;
(iv) an officer, or employee of such international organizations, and the members of his/her immediate family;
(v) an attendant, servant, or personal employee of any such representative, officer, or employee, and the members of the immediate family of such attendants, servants, and personal employees. Section 101(a)(15)(G), 8 USC 1101(a)(15)(G).
The regulations governing this nonimmigrant visa category may be found at 8 CFR Sec. 214.2(g)(1) and set forth the procedures for applying for the G nonimmigrant visa category.