Most countries need a visa.
Nationals of Denmark
Finland, Japan, Norway, South Korea and Sweden can stay for up to 15 days without a visa.
Passport holders from Thailand, Malaysia, Singapore, Indonesia, Philippines and Laos do not require a visa for visits of up to 30 days.
Tourist visas are good for thirty days and may be extended after your arrival in Vietnam. Fees vary from embassy to embassy; about $50 in Bangkok and $85 in Washington, for example. A double entry visa is also available for tourists making side trips from Vietnam to destinations in Thailand, Cambodia and Laos.
A visa on arrival service is offered by various travel agents on the web. This is more of a pre-approval visa service and you may be limited by arrival dates and arrival locations.
Vietnam Passport and Visa Guide
Vietnamese embassies
