Assassination missions are provided to Niko by The Fixer. Visit the payphone on the western edge of Port Tudor at the Odhner Avenue-Traeger Road. A cutscene plays that depicts The Fixer briefing Niko on the mission at end. These missions are not an integral part of the storyline, but do count towards 100% completion.

After Phil Bell's first mission, Phil will call Niko asking if he is interested in doing some side jobs. The Fixer wants Niko to take out some enemies. Go to the designated payphone indicated by the crosshair icon to initiate an assassination mission. Once all of the missions are complete, The Fixer will contact Niko to express his satisfaction but tell him that he needs to cut ties. He will not appear again.

• Water Hazard: Find the targets, members of the Lost Brotherhood or Northwood Dominican Drug Dealers, on a boat anchored off shore. Use an RPG to take them down with the ship.
• Migration Control: Use an RPG to take down the helicopter once the targets have boarded.
• Derelict Target: Take out the three heavily guarded units of the Triads and Russian Mafia in Alderney City. The police get involved regardless of your actions, which makes this a tough mission. This forces you to move quickly and/or kill cops, which brings your wanted level up to four stars. The easiest way to succeed at this mission is to get a helicopter, head to street, snipe two of the targets, and fly to the roof and shoot the third member through the partially destroyed building. Fly away as soon as you attract the attention of the police.
• Bailing Out for Good: Kill the target outside the police station as he is bailing out.
• Hook, Line and Sinker: Use a boat to get close to the target, the driver of another boat. Shoot the boat untli it explodes.
• R.U.B. Down: Head south to find the target in the Acter Industrial Park. The three targets are all on bikes. Use a grenade to take them all out at once.
• Industrial Action: Three more targets at the industrial park are under guard. Use a sniper rifle from the north side to take them out before anyone realizes what is happening.
• Taken Out: Take a car that handles well and head towards the convoy. Take everyone out with your SMG or Carbine Rifle.