The best thing to do is to know the rules. Getting a visa to visit the U.S. for business or pleasure can be difficult for some travelers. Before we get to the rules, the first issue is to verify whether your family member needs a visa. For those individuals who are nationals or citizens of Visa Waiver countries, a visa is not required in most cases and they can apply online under the Electronic System for Travel Authorization (ESTA). The State Department provides a list of Visa Waiver countries and instructions. If your family member is not a national or a citizen of a Visa Waiver country, then she needs to request a visa from her local U.S. consulate.
Once you determine that she does need a visa, the greatest areas of concern that can arise during the interview generally fall into these 3 categories: