Directional influence, abbreviated DI, is the control the receiver of an attack has over his or her trajectory. Each attack sends its target in a particular direction, depending on the attack itself and on the target's weight and falling speed; DI can be used to alter, but not completely negate, this trajectory. This change, however, can be vital to surviving high-power attacks such as Fox's up smash, and for escaping combos such as Jigglypuff's Space Animal Slayer among many others. DI is most useful to make the character move into a trajectory being as far to the blast line as possible. DI differs upon the character, like Lucario, who arguably has among the most useful DI in Super Smash Bros. Brawl.
In Super Smash Bros. Brawl, the following are the most common ways of utilizing directional influence for surviving KO attacks:
- Hold the control stick diagonally upwards in the opposite direction the character has been knocked.
- Hold the control stick either left or right.
The player can DI by pressing the control stick in any direction during or just after being hit by an attack. There are three types of directional influence: normal DI (often simply referred to as "DI"), Smash DI, and Automatic Smash DI. The type of DI changes depending on when the player presses the control stick.
 DI in the Super Smash Bros. series
In Super Smash Bros., Smash directional influence is the only type of DI that exists. This means that the only moves that are easy to DI out of are multi-hit attacks such as Fox's down aerial or Samus's Screw Attack. Due to this and the fact that attacks have high hitstun, combos are often easier to perform in Super Smash Bros. than in Super Smash Bros. Melee or Super Smash Bros. Brawl.
In Super Smash Bros. Brawl, DI is not as useful as it was in Super Smash Bros. Melee, but it is easier to perform due to longer hitlag. Momentum Canceling, a technique unique to the former, is of very high utility and this coupled with DI enables players to survive high-knockback attacks at relatively high damage percentages for characters who can utilize it.