How does a country qualify to participate in the Visa Waiver Program (VWP)?
Among these criteria are requirements that:
Governments provide reciprocal visa-free travel for U.S. citizens (90 days for tourism or business purposes);
Governments issue secure machine-readable passports that satisfy internationally accepted standards;
Governments certify that they have a program to incorporate biometric identifiers into their passports in accordance with International Civil Aviation Organization standards;
Governments certify that they report the theft of blank passports on a timely basis to the U.S. Government, and do so in practice;
The country must have a very low nonimmigrant refusal rate (as explained in Section 217 (c)(2)(A) of the Immigration and Nationality Act); and
The incidence of nationals of the country traveling as nonimmigrant visitors who are denied admission, withdraw their application, and violate the terms of a VWP admission is less than two percent of the total number of nonimmigrant nationals traveling to the U.S. during the previous fiscal year.
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Specific factors to be considered in such a review are not established in the legislation. However, in the past the following types of issues have been considered:
Security of a country’s passport application, production and delivery processes;
Security of passports and other documents used to demonstrate identity and citizenship, and incidence of fraud or misuse involving such documents;
Nationality and citizenship laws, and application of such laws;
Existence of security and law enforcement threats in the country (terrorist activities, organized crime, money laundering, human and drug trafficking, etc.), and efforts to address such threats;
Immigration controls and alien smuggling activities in the country, and efforts to address such threats;
Stability of the government politically and economically;
Degree of cooperation with the U.S. and other international partners on law enforcement issues, including extradition.
http://www.travel.state.gov/visa/tem...hout_1255.html