Here is the full list of all 36 Tom Clancy's Rainbow Six Vegas achievements worth 1,000 gamerscore.
Complete the single player Story Mode at Realistic difficulty
Cooperatively complete all Terrorist Hunt missions
Complete a Cooperative Story mission with at least one other player
Complete all maps in splitscreen T-Hunt at Realistic difficulty
100 total player kills in any adversarial mode
Complete all maps of splitscreen Terrorist Hunt on Normal difficulty
Complete a Cooperative T-Hunt mission with at least one other player
5 consecutive player kills without dying
Achieve the rank of Private 1st Class
Kill 150 terrorists using only a Pistol
Completed Nevada Dam in single player Story Mode
Used all Gadgets at least once in single player Story
Completed Dante’s Casino in single player Story Mode
Completed Vertigo Spire in single player Story Mode
Completed Downtown Vegas in single player Story Mode
Kill 500 terrorists online or offline
Completed Calypso Casino in single player Story Mode
Completed Border Town in single player Story Mode
10 kills using a Sniper rifle in an online ranked match
10 consecutive player kills without dying
Kill 50 players using Explosives only
Play all maps of every Adversarial game mode
Leading contributor of kills for the Defenders in a winning Attack & Defend ranked match
Be the only remaining player in a ranked online match of Survival
Most kills in a ranked online Sharpshooter match
Most kills in a winning online ranked match of Team Survival
Most kills in a winning online ranked match of Team Sharpshooter
Rescue all hostages in an Attack & Defend mission in under 5 minutes
Defuse the bomb within 2 minutes in Attack & Defend
Recover the Intel in Attack & Defend within 2 minutes
Deposit the canister and kill an enemy canister carrier in the same Retrieval match
Host a 16-player match
Achieve the rank of Elite
Achieve the rank of Lieutenant 2nd Class
Cooperatively complete the Story Mode
Used the Xbox Live Vision to create a character with your appearance