If you want to stay for more time, you can apply for the renewal of B-1 visa, which can be renewed to 6 months at most once.

According to the length of your activity in US, the visa may usually be admitted for not more than 3 months. For some special cases, it will valid for half a year, but no more than a year.

Ties refer to all kinds of relations that making you live in your mother country or other places, such as they have a residence outside the US, as well as, other strong economic, financial, social, and family ties to their home country, which will insure their return abroad at the end of the visit.

It is important to demonstrate the following points to the consular officer:

1) The purpose of their trip is to enter the US for business, pleasure, or medical treatment;

2) They plan to remain for a specific, temporary period of time; and

3) They have strong ties to their own country.

B-1 visa is available for the following people:

1) An individual traveling to the United States to take part in an exhibition, set up an exhibition booth, display samples, sign contracts, and take orders for merchandise produced in and delivered from the alien��s foreign country;

2) Individuals participating in a voluntary service program which benefits a U.S. local community, who establish that they are a member of, and have a commitment to, a particular recognized religious or nonprofit charitable organization;

3) Individuals who will install, service or repair commercial or industrial equipment or machinery sold by a company in the alien��s foreign country to a buyer in the United States;

4) Individuals traveling to the United States in connection with a speaking engagement;

5) Participants in scientific, educational, professional, or business conventions, conferences or seminars;

6) Individuals who will engage in independent research;

7) Individuals traveling to the United States to survey potential sites for a business and/or to lease premises;

8) Individuls coming for an elective clerkship which affords practical experience and instruction in the various disciplines of medicine under the supervision and direction of faculty physicians at a U.S. medical school's hospital;

9) Individuals temporarily resident in the United States who will be working from home as computer programmers for foreign based companies;

10) Individuals performing missionary work on behalf of a religious denomination, to engage in an evangelical tour and do not plan to take an appointment with any one church you may be eligible, or to preach in the United States for a temporary period;

11) Individuals participating in a voluntary service program which benefits a U.S. local community;

12) An amateur, or group of amateurs performing in a social and/or charitable context, or as a competitor in a talent show or contest;

13) A professional entertainer may be eligible, unless an O visa or P visa is appropriate;

14) An amateur athlete or group of athletes competing in an athletic event for which they will receive no payment, other than incidental expenses;

15) Professional athletes, such as golfers and auto racers, who receive no salary or payment other than prize money for his/her participation in a tournament or sporting event.

B visa is a category of visitor visa, a nonimmigrant visa for persons desiring to enter the United States temporarily for business (B-1) or for pleasure or medical treatment (B-2).