The visa requirements for visiting Vietnam vary depending on your nationality, the purpose of your visit, and the length of your stay. Here's an overview:

1. Visa Exemption: Some nationalities are exempt from obtaining a visa for short visits to Vietnam. The duration of visa exemption and conditions vary, so it's essential to check the latest regulations specific to your country.

2. Visa on Arrival (VOA): For travelers arriving by air, the most common way to obtain a visa for Vietnam is through the Visa on Arrival (VOA) process. This requires obtaining a pre-approved visa letter from a Vietnamese travel agency or sponsor before traveling. Upon arrival at one of Vietnam's international airports, travelers present the approval letter, passport photos, and the visa stamping fee to receive their visa at the immigration counter.

3. E-Visa: Vietnam also offers an E-Visa option for citizens of certain countries. This allows travelers to apply for a visa online through the official website of the Vietnam Immigration Department. Once approved, the E-Visa is electronically linked to the traveler's passport and allows entry through designated ports of entry.

4. Embassy or Consulate: Travelers can also apply for a visa directly at a Vietnamese embassy or consulate in their home country before traveling. This typically involves submitting an application form, passport photos, and the required supporting documents, along with the applicable visa fee.

5. Visa Extensions: For those wishing to extend their stay in Vietnam beyond the initial visa validity, it's possible to apply for a visa extension through the Vietnam Immigration Department. This process typically requires submitting an application form, passport photos, and payment of the extension fee.