lag

a modification of a logical relationship that directs a delay of the successor task. For example, in a finish-to-start dependency with a 10-day lag, the successor activity can start 10 days after the predecessor has finished. See also lead.

late finish date (LF)

in the critical path method, the latest possible point in time that an activity can be completed without delaying a specified milestone (usually the project finish date).

late start date (LS)

in the critical path method, the latest possible point in time that an activity can begin without delaying a specified milestone (usually the project finish date).

lead

a modification of a logical relationship that allows an acceleration of the successor task. For example, in a finish-to-start dependency with a 10-day lead, the successor activity can start 10 days before the predecessor has finished. See also lag.

logic

the collection of activity dependencies that make up a project network diagram.

logic diagram

see network diagram.

logical relationship

a dependency between two project activities. The four possible types of logical relationships are:

• finish-to-start—the "from" activity must finish before the "to" activity can start.

• finish-to-finish—the "from" activity must finish before the "to" activity can finish.

• start-to-start—the "from" activity must start before the "to" activity can start.

• start-to-finish—the "from" activity must start before the "to" activity can finish.

Finish-to-start is defined as the standard (or default) logical relationship.

loop

a network path that passes the same node twice. Loops cannot be analyzed by using traditional network analysis techniques such as CPM and PERT. Loops are allowed in GERT.