The Vietnam Add-on for Battlefield: Bad Company 2 has 10 achievements worth 250 gamerscore.
Get 50 kills with the Huey
Get gold stars on all primary Vietnam weapons
Get silver stars on all primary Vietnam weapons
Get 100 kills with Vietnam tanks
Win a round of either Rush or Conquest on all four Vietnam levels
Get a kill with all Vietnam vehicles
Finish first on the scoreboard on any Vietnam level
Get 20 kills with the flamethrower
Destroy a Hannoi Hannah propaganda speaker
Achieve the best squad award on Operation Hastings