Foreign nationals traveling to the United States for a temporary visit or business trip may need a B1 or B2 visa if their countries of origin do not participate in the Visa Waiver Program. As a part of the application for the B1 or B2 visa, documentation corroborating the purpose of the trip must be presented. While there is no set requirement for a letter, the State Department requires consular officers to verify evidence which shows the purpose of the trip and intent to depart the United States in addition to ensuring that arrangements have been made to cover the costs of the trip. For applicants that may not have sufficient funds to cover the trip to the States, evidence, such as a supporting letter, can be shown to substantiate that a third party, such as a friend or relative, will provide support. Applicants will also be prompted to provide documentation confirming the purpose of the trip. In addition, documentation that the applicant plans to return home and that the applicant has binding obligations at home, such as employment or family.