420 Part III • Acquiring Information Systems
A DBCGFH
610
435(^73)
2
2
3
I
E
Critical Path = ACGHI (19 days)
FIGURE 11.6 Critical Path Method (CPM) Example (Reprinted
from Fuller et al., 2008)
Planning Documents
Two documents are typically created from the project plan-
ning phase: a statement of work (SOW)for the customer
and a project plan to be used by the project manager to
guide, monitor, and control the execution of the project plan.
The SOW document is a high-level document that
describes what the project will deliver and when. It is in
effect a contract between the project manager and the exec-
utive sponsor. It therefore can be used as a high-level guide
for business managers to plan for their own unit implemen-
tation as well as to monitor the project’s progress toward
the project goals of on-time completion within budget.
All program managers or committees that oversee
the project typically review the project plan. For example,
a program manager and other IT project managers may ini-
tially review the project plan, and then a project oversight
committee of business managers and IS leaders may be
asked to endorse it.
Two types of project management charts are also typ-
ically developed during the planning phase and used during
project execution: (1) PERT or CPM charts and (2) Gantt
charts. These are two complementary techniques for proj-
ect scheduling and resource planning, as described next.
A PERT chart (a Program Evaluation and Review
Technique developed for a missile/submarine project in
1958) graphically models the sequence of project tasks and
their interrelationships using a flowchart diagram. An
alternative method called CPM (Critical Path Method) was
developed by DuPont about the same time. As shown in
Figure 11.6, each major task is represented as a symbol
(here circles), arrows are used to show predecessor and suc-
cessor tasks, and the time period to accomplish each task
(here in days). By examining these dependencies (or critical
paths), the sequence of activities that will take the longest
to complete can be calculated (here the path at the top,
19 days). Any delays in completing the activities on this
critical path will result in slippage on the project schedule.
Researchers have found that projects in which CPM or
PERT techniques are used are less likely to have cost and
schedule overruns (Meredith and Mantel, 1989).
A Gantt chart graphically depicts the estimated times
(and later, the actual times) for each project task against a
horizontal timescale. Tasks are presented in a logical order
along with a bar graph depicting the estimated time
duration for each task on an appropriate linear calendar
(i.e., minutes, hours, days, or weeks) for the number of
months and years planned for the life cycle of the project
(see Figure 11.7). The precedence relationships in the
PERT/CPM chart are reflected in the start and end dates of
the activities, and overlapping tasks can be easily seen.
Gantt charts are therefore particularly useful for displaying
a project schedule and for tracking the progress of a set of
tasks against the project plan (as discussed in the “Project
Execution and Control” section next). An important project
management skill is to determine at what level of detail to
plan the project tasks. Too much detail can be stifling and
result in too much time being spent on tracking rather than
on more critical project tasks. Too little detail can result in
inadequate project management controls and both missed
deadlines and cost overruns.Project Execution and Control
The documents described in the Planning section are best
recognized as living documents that need to be refined and
reassessed throughout the life of the project. The objective
of the execution process is to effectively coordinate all
resources as the project planis carried out. Measuring
variances from what was planned versus what progress is
actually achieved is part of the controlling process.
In large, complex projects, the planning activities
still continue after a project team has been selected and
some initial tasks have been undertaken, and the revised
plan goes through the same endorsement procedures a few
months into the project, as described previously.