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Mile in Their Shoes is a perk in the Fallout: New Vegas add-on Old World Blues.
This perk gives the Courier a bonus of +1 Perception, +5 Poison Resistance and +5 Sneak for 4 minutes after consuming nightstalker squeezin's.
The Poison Resistance gained by this perk is useless if the player character has the Heartless perk, which grants complete immunity to poison.
The name of the perk is based on the old proverb, "Before you criticize someone, walk a mile in their shoes," which is to say, to attempt to understand a person before judging them.