Source: The U.S. Department of State
This "visitor" visa is a nonimmigrant visa for persons desiring to enter the U.S. temporarily for business (B-1) and for pleasure or medical treatment (B-2). For example, if the purpose of your planned travel is recreational in nature, including tourism, amusement, visits with friends or relatives, rest, medical treatment, and activities of a fraternal, social, or service nature, then a vistor visa (B-2) would be the appropriate type of visa for your travel. As additional examples, if the purpose for your planned travel is to consult with business associates, travel for a scientific, educational, professional or business convention, or conference on specific dates, settle an estate, or negotiate a contract, then a business (B-1) visitor visa would be the appropriate type of visa for your travel.
Current maximum stay in the U.S. for B visas is one year: most are admitted for 6 months or less.
Requirement for Visitors to UC Berkeley Departments
UC Berkeley guidelines require all international visitors participating in research activities for at least 21 days to come as J-1 Exchange Visitors. While U.S. immigration inspectors have wide discretion in granting entry to the U.S., they do not view the B1/B2 as appropriate for someone coming to a University to conduct any research especially if it is full-time for an extended period. In addition, many embassies and consulates now require the J-1 visa be used for such purposes. It is recommended that prospective researchers consult with the academic department at UC Berkeley in conjunction with Berkeley International Office to determine the most appropriate status for the proposed visit.
The Visa Waiver Program (a.k.a. WT and WB Visas)
Travelers coming to the U.S. for tourism or business for 90 days or less from qualified countries may be eligible to visit the U.S. without a visa if they meet the visa waiver program requirements. See the Visa Waiver Program to learn more, and find out if you meet the visa waiver requirements.
Payments to B-1, B-2, WB and WT Status Holders
Under certain conditions, people holding these types of status may be paid by a U.S. institution or a nonprofit or governmental organization, honoraria and associated incidental expenses for "usual academic activity." Please check with your host department before choosing the B or Visa Waiver Program to be sure you are eligible to be paid or reimbursed.