along with Work Breakdown Structure (WBS), earned value performance
measurement (EVPM), and the precedence diagram method (PDM), make up the
big four of project management. WBS identifies activities that you need
to accomplish, a Gantt chart or PDM network schedules these activities
and earned value evaluates performance and communicates progress.
Gantt chart may be the most popular tool associated with project
management. It is a timeline chart. A Gantt chart defines start times and
durations for each project task. Also, it portrays how tasks are
positioned by showing how they occur simultaneously, sequentially, and
An Overview of Gantt Charts
charts are valued as a way to quickly and clearly communicate your
project's schedule and progress.
core project management tool, a Gantt chart provides a graphical
illustration of a schedule that helps you plan, coordinate and control
tasks for your project. Gantt charts are traditional management aids used
to schedule projects. They may be simple schedules that you develop on
graph paper or complex and sophisticated versions that you create with
of a Gantt chart as a matrix that contains project work. Horizontal bars
represent planned start and finish dates for each activity.
purpose of a Gantt chart is to organize and clarify planned use of
resources and occurrence of activities in a time-oriented framework.
The Mechanics of a Gantt chart
overriding intent of a Gantt chart is to organize and clarify that actual
of planned use of resources by creating horizontal bars to represent
activities and exercising control against the bars.
Gantt charts use forward scheduling logic. Use forward scheduling by
setting today's date as Day Zero and making time estimates for each
activity. Forward scheduling provide you with an opportunity to create
trial-and-error schedules. This supplies you with ideas of what different
arrangements of tasks may involve. Once you have an acceptable
arrangement, identify relationships for all activities and construct and
extend each bar into the future.
progress bars to exercise control. Please review the following for an
4.1. Gantt chart and progress bars
Milestones are important checkpoints. They are typically part of your
project's critical path. They represent important events to include on
your Gantt chart that are not tasks. More correctly, milestones signify
zero-duration stages of your project. When milestone dates are not met,
your entire project schedule suffers.
possible (probable) that milestones change as your project progresses.
Gantt Chart Construction
When you construct a Gantt chart, use a common format. Some flexibility
is permissible under special circumstances.
get started, make sure to use a WBS to identify all activities or work
packages that you need to accomplish to make your project successful.
Remember, a WBS does not sequence events. Sequencing tasks is the job for
a Gantt chart.
Follow these steps:
Identify project activities, in order of their occurrence, on the left
side of your project form.
Develop estimates for each activity.
Create time buckets across the top of your page that represent the
appropriate period of time.
each activity, indicate start and finish times by creating task bars and
by filling in/highlighting across each row.
Assign a milestone.
your Gantt chart with all key stakeholders (including your project team).
Monitor your project and create progress bars.
charts do not easily reveal a project's critical path.
charts do not clearly identify a behind schedule condition.
charts present a challenge for recording progress.
are no widely accepted standards for Gantt charts.
charts require a great deal of updating and posting.
charts are difficult to use to respond to customer requests for
accelerated project delivery.