A Successor Activity is a dependent activity that logically comes after another activity in a schedule.

It is linked to a predecessor activity through a logical relationship that dictates the order in which tasks are performed. The timing and sequencing of the successor are determined by the relationship type—such as finish-to-start or start-to-start—which governs how and when the successor may begin or end relative to its predecessor.

Key Characteristics

  • Dependent Sequence – Follows another activity in the schedule
  • Controlled by Logical Relationships – May start or finish based on the predecessor’s progress
  • Part of the Schedule Network – Integral to critical path and float calculations
  • Supports Structured Planning – Helps define realistic, constraint-based task flows

Example Scenarios

  • Testing (successor) cannot begin until development (predecessor) is complete
  • Data import (successor) starts as soon as the system setup (predecessor) begins
  • Deployment (successor) finishes only after final approval (predecessor) starts

Example Successor Activity

gantt
    title Successor Activity Example
    dateFormat  YYYY-MM-DD
    axisFormat  %b %d

    section Project Schedule
    Predecessor Activity :a1, 2025-04-15, 3d
    Successor Activity    :a2, after a1, 4d

Role in Project Scheduling

  • Enables Dependency Modeling – Clarifies execution order and coordination
  • Supports Critical Path Analysis – Helps identify time-sensitive chains of activities
  • Drives Task Timing – Successor start and finish dates depend on predecessor status
  • Feeds Performance Tracking – Helps analyze schedule variance and forecast delays

See also: Predecessor Activity, Summary Activity, Logical Relationship, Start-to-Start, Finish-to-Start.