SSI defines a Driving Predecessor as an activity that has zero days of Driving Slack to the successor activity currently under examination. In other words, any delay to the start or finish of the driving predecessor would directly impact the timing of the successor being examined. The specific impact depends on the type of dependency between the two tasks:
• Finish-to-Start (FS): A delay in the Finish of the predecessor will delay the Start of the successor.
• Finish-to-Finish (FF): A delay in the Finish of the predecessor will delay the Finish of the successor.
• Start-to-Start (SS): A delay in the Start of the predecessor will delay the Start of the successor.
• Start-to-Finish (SF): A delay in the Start of the predecessor will delay the Finish of the successor.
Driven Successor
SSI defines a Driven Successor as a successor activity to which the predecessor activity currently under examination has zero days of Driving Slack to. In other words, any delay to the start or finish of the predecessor under examination would directly impact the timing of the successor task. The specific impact depends on the type of dependency between the two tasks:
• Finish-to-Start (FS): A delay in the Finish of the predecessor will delay the Start of the successor.
• Finish-to-Finish (FF): A delay in the Finish of the predecessor will delay the Finish of the successor.
• Start-to-Start (SS): A delay in the Start of the predecessor will delay the Start of the successor.
• Start-to-Finish (SF): A delay in the Start of the predecessor will delay the Finish of the successor.
