Lag

Lag is a positive delay added to a task dependency link. When a dependency carries lag, the successor task cannot begin (or finish) until the specified lag time has elapsed after the predecessor reaches its trigger event. Lag models mandatory waiting periods that exist independently of how much work is assigned — regulatory review windows, material curing time, shipping lead times, or approval cycles that the schedule must honor.

How Lag Works

In a standard Finish-to-Start (FS) dependency, Task B begins as soon as Task A finishes. Add three days of lag — written as FS+3d — and Task B must wait three days after Task A's finish date before it can start. Those three days appear on the Gantt chart as a visible gap between the end of Task A's bar and the start of Task B's bar. The lag days are not work on either task; they are dead time required by the process.

Lag is expressed as a positive duration in whatever time units the schedule uses — hours, days, or weeks. The scheduling engine counts only working time when applying lag, so a 3-day lag added to an FS link between two weekday tasks skips over any weekend days in between.

Lag Across All Four Link Types

Lag can be applied to any of the four standard dependency types:

• FS+lag — successor cannot start until the lag period after the predecessor finishes
• SS+lag — successor cannot start until the lag period after the predecessor starts
• FF+lag — successor cannot finish until the lag period after the predecessor finishes
• SF+lag — successor cannot finish until the lag period after the predecessor starts

The most common combination is FS+lag, but SS+lag is frequently used to model sequential ramp-ups where the second activity starts a fixed time after the first, regardless of when the first finishes.

Lag and the Critical Path

Lag contributes to project duration just as task duration does. A 5-day task with a 3-day FS lag before its successor adds 8 days to that chain in the schedule. When the link carrying lag is on the critical path, reducing the lag — by negotiating a faster review, choosing a faster-curing material, or expediting shipping — can shorten the project end date without touching any task duration.

Lag in Maverick

Maverick supports lag on all four dependency link types. You set lag when creating or editing a predecessor relationship in the task's Properties panel. The Gantt chart immediately reflects the gap between predecessor and successor bars, and the critical path recalculates to account for the lag value. For a deeper look at dependency types and how lag interacts with each, see the guide: Task Link Relationships.

Related Terms

Task Dependency  ·  Predecessor  ·  Critical Path  ·  Float  ·  Schedule Compression