In World at War  multiplayer, dogs can be called in by a player after killing seven enemy players consecutively without dying. The dogs spawn and attack enemy players on the map for 60 seconds. Friendly dogs appear as German Shepherds and enemy dogs are black Belgian malinois.

The dogs can be killed, but will continue to respawn until the 60 second cycle has ended. Dogs attack by lunging and biting at enemy players. Players can survive up two dog lunges before dying in Core, but only one in Hardcore. Killing a dog will give a player 2-3 EXP depending on the game mode, but will not count as a kill or an assist. However, in Team Deathmatch and Free-for-All players score 3 and 2 points respectively, making it possible to actually win the game with fewer kills than would otherwise be necessary. For this reason, it can actually be detrimental to call in Dogs in these gametypes. Dogs rarely go into water and cannot climb ladders. Dogs also cannot attack players in tanks.

The Attack Dogs make a return in Call of Duty: Black Ops, and have been upgraded to an 11-killstreak reward in Multiplayer. German Shepherds (friendly) or Belgian Shepherd Malinois (enemy) will spawn for a set period of time after activation. Four dogs initially spawn, with four reserve dogs. As the first four are killed, they are replaced from the reserves, giving a maximum of eight dogs over the time the kill streak is active. The dogs can now kill in one bite, likely due to the challenging task of acquiring 11 kills. Dogs are also attracted to gunfire, so a good thing to keep in mind would be to try and leave things quiet for a while. Ghost Pro does not make the player invisible to them. The most effective ways to counter dogs are to camp in an area with long range sight-lines and preferably with a wall behind the player in order to be able to gun them down or climb to an area only accessible by a ladder. 

Trivia 

• Although dogs cannot climb ladders, they have been known to leap six-foot high to get on top of objects, such as the grassy-jungle-like walls on "Courtyard" and can even jump the entire ladder on the balcony in "Dome."
• Dogs are affected by Tabun Gas. Proof of this can easily be seen in the Kill Cam if a player gets killed by a dog hit by such a grenade. The dog's vision will be distorted in much the same way that a human player's would be.
• If a dog jumps off the map it may fly back up a few seconds after falling, however this is rare for either event to happen as the AI is programmed not to do this
• In Nuketown, if the player calls in dogs and then calls in a Chopper Gunner, the player can see the dogs leaving the map (climbing the fence, etc.) and going into some boulders when the dogs' time has expired.
• On the multiplayer level Berlin Wall, dogs can travel through the red zone without being shot by the guard towers.
• Nova Gas will affect dogs. Dogs in the gas will stop and scratch at their eyes for a moment before continuing their attack.
• If an enemy player hides behind the player that called the attack dogs in, the dogs will simply stand there and not attack.
• It is possible for the player to be killed by their own dog. If the player walks in front of a friendly attacking dog the player will die. The kill feed states that the player committed suicide and shows a dog emblem.