Lead

Lead is the mirror image of Lag: instead of delaying the successor, it pulls it forward. A typical example is preparing a test flight report beginning five days before the flight test series completes. It is entered as a negative amount of time on the relationship, which is why it is often called negative Lag. Leads warrant more caution than Lags — the better approach is usually to break the predecessor into smaller tasks at real logical break points rather than overlapping them, and the government applies strict tolerances to the use of Leads. The reason is that a Lead compresses the schedule by assertion rather than by modeling how the work actually flows.

Why it matters

A Lead makes a schedule finish sooner without changing any of the underlying work, which is precisely why it attracts scrutiny. Used honestly it captures genuine overlap; used carelessly it manufactures schedule that isn't there. If the overlap is real, it can usually be modeled by splitting the predecessor into the part the successor actually waits for and the part it doesn't.

See also

FAQ