Tom Clancy's Rainbow Six 3 Cheats

Conserving Ammunition:
Reload after every fire-fight even if you have 22 rounds remaining.
By doing this you will have enough ammunition for the long fire-fights and levels.

Save the game when you diffuse a bomb save a hostage or do other
important goals so then when you or your team members get killed
you can go to load and every thing will be back the way it was and
you can be ready to waste the guy who got you.