The Visa Waiver Program (VWP) allows citizens of specific countries to travel to the United States for tourism, business, or transit for up to 90 days without obtaining a visa. While the program offers convenience, there are important dos and don'ts that travelers should keep in mind to ensure a smooth and lawful visit.

Before planning your trip under the VWP, verify that your country of citizenship is on the list of eligible countries. Additionally, you must have an Electronic System for Travel Authorization (ESTA) approval before boarding your flight to the U.S. It's crucial to apply for ESTA well in advance of your travel date, as last-minute applications can result in delays or denials. The VWP allows you to stay in the United States for a maximum of 90 days. This period cannot be extended, and you must leave the country on or before the 90th day. Overstaying your welcome can have serious consequences, including being barred from future entry into the U.S. under the VWP or even under a regular visa. 

The VWP is intended for specific purposes such as tourism, business meetings, or transit. You may also engage in short-term educational courses that do not count for credit towards a degree. However, working, studying for credit, or participating in long-term training programs are not allowed under the VWP. Engaging in prohibited activities can lead to immediate deportation and bans on future entry. Also, it is good to ensure that your passport is valid for the duration of your stay in the U.S. Some countries require that passports be valid for at least six months beyond your planned stay, although the U.S. has agreements with certain countries that waive this requirement. 

Unlike other visa categories, the VWP does not allow for extensions of stay or changes in visa status. Attempting to extend your stay beyond the 90-day limit or seeking to change your status to a different visa category while in the U.S. under the VWP is not permitted. If you wish to stay longer or change your visa status, you must leave the U.S. and apply for the appropriate visa from your home country. Lastly, the VWP is not intended for frequent, back-to-back visits that effectively extend your stay in the U.S. If you leave the U.S. and immediately return, CBP officers may suspect that you are trying to circumvent the 90-day limit, which could lead to your entry being denied. To avoid this, ensure that your trips are genuinely short-term and that you spend a reasonable amount of time outside the U.S. between visits.