3e SRD:Evasion and Improved Evasion
From D&D Wiki
|This material is published under the OGL|
Evasion and Improved Evasion
If subjected to an attack that allows a Reflex save for half damage, a character with evasion takes no damage on a successful save.
As with a Reflex save for any creature, a character must have room to move in order to evade. A bound character or one in a completely restrictive area (crawling through a 2 1/2-foot-wide shaft, for example) cannot use evasion.
As with a Reflex save for any creature, evasion is a reflexive ability. The character need not know that the attack is coming to use evasion.
Improved evasion is like evasion, except that even on a failed saving throw the character takes only half damage.