Project Management Software Primer: ABCs of Project Management Software
Project management software performs to a rather specific set of four activities related to making sure that you successfully complete a project:
1. Organizing and showing the individual pieces making up a project
2. Showing the timing of tasks: both the time required to complete tasks and the time tasks start and stop
3. Identifying and allocating the resources needed to complete a project
4. Comparing the planned outcome with the actual outcome. Comparisons are usually made in three areas: time spent, resources required, and money spent.
For an example of these four components of project management, suppose that you decide to spruce up the interior of your apartment. The following section explains how you could set up and manage your project.
NOTE: The example that follows is intentionally simple. The simplicity makes it easy for you to concentrate on the project management issues involved and not the project.
Organizing the Pieces Making Up the Project with Project Management Software
Project management software breaks the project into pieces and noting any relationships among them. You might, for example, list six steps for the painting project:
1. Wash the surfaces
2. Plug any holes with patching compound
3. Tape window and door frames to protect them
4. Buy the supplies and tools you need
5. Paint the walls
6. Clean up after you finish
Each of these steps is called a task. Clearly, you can perform some tasks at the same time. For example, the first four tasks can probably occur in any order. If someone helps, these tasks can even occur at the same time.
However, you need to complete some tasks before you can begin others. For example, you need to complete the first four tasks before you can begin to paint. And you should probably clean up last. Project management software calls these relationships are called dependencies because one task depends on another. These relationships are also called links because the start of one task is linked to the finish of another task. When one task depends on another, the task that you must finish first is called the predecessor. The task that must follow the predecessor is called the successor.
Some tasks consist of still smaller tasks or pieces. When a task is made up of multiple parts, these parts are called subtasks. For example, you can divide the cleaning-up task into four additional tasks:
1. Locate any spills and remove them
2. Clean the brushes
3. Remove the masking tape
4. Put away things away
One way project management software organizes the pieces of a project is by creating a list of tasks and subtasks. But project management software can organize a project in other ways, too.
For example, project management software can organize project information with a PERT chart, as illustrated in the drawing in Figure 1-1. Figure 1-1 graphically depicts the three main tasks you need to complete for the imaginary example project.
Figure 1-1: An example PERT chart such as project management software might produce.
PERT is an acronym that stands for Program Evaluation and Review Technique. Project management software uses a PERT chart to show the tasks and the task dependencies of a project. A PERT chart also shows the relationships among tasks. For example, in Figure 1-1, the lines connecting the boxes show the order in which the tasks must be performed.
Listing project tasks and using a PERT chart typically makes a project easier to organize and manage. One big benefit, of course, is that you remember what you need to do to complete the project.
You can also benefit from using a PERT chart because it allows you to visually organize and inspect the relationships among tasks. After reviewing Figure 1-1, for example, you may decide that other dependencies or links exist. Certainly, a PERT chart makes reviewing task dependencies easier.
These two benefits become more important when you use project management software for projects with greater numbers of tasks. Part of the reason is that inadvertently missing a task or dependency is easier when more tasks are involved. Another reason is that when you have large projects, you often tap the skills of more people. If you use project management software for a project with several dozen, several hundred, or several thousand people, achieving project success requires that everyone knows what the project entails and the order in which tasks should be completed.
Showing the Timing of the Tasks with Project Management Software
Showing the timing of tasks is the second part of the project-management activity. The timing of tasks consists of two parts: figuring out how much time a task takes and figuring out when a task starts and finishes.
Estimating Task and Project Durations
To show the timing of tasks, you first estimate the amount of time that each task will take. Suppose that you decide to organize the example project, using the six main tasks. You might make the following estimates:
Washing—3 hours
Plugging—1 hour
Taping—1 hour
Buying—.5 hour
Painting—4 hours
Cleaning—.5 hour
The time taken to complete a task is called its duration. For example, the duration of the washing task equals 3 hours, and the duration of the plugging task equals 1 hour.
Some pieces of a project aren’t really tasks at all, because their duration equals zero. When the duration of a piece equals zero, the piece is called a milestone. Typically, milestones represent events that don’t require work—but they are significant points in the project’s schedule or life. For example, the Start and End boxes in Figure 1-1 represent milestones.
After you estimate task durations, you can determine how long the project will take to finish by identifying the paths through a project on a PERT chart. To move from the start of the project to the end of the project, you must follow a path. For example, the first path is to start the project with the Washing task, move to the Painting task, and then move to the Cleaning task.
Figure 1-1, in fact, shows four paths, or routes, through the PERT chart. If the term path seems confusing, place your finger on the Start box in Figure 1-1 and trace the lines that connect the Start box to the Wash box, the Wash box to the Paint box, the Paint box to the Clean box, and the Clean box to the End box. What you trace with your finger is the first of the four paths.
Each path has a duration that equals the total of the individual task durations making up the path. You can calculate path durations of the other four tasks, too, by tracing the various paths through the PERT chart.
When you know the durations of each of the paths through the project, you know how long the project will take to finish. Assuming you have at least one other person helping you with the first four tasks of the project, you can determine a critical path, or an estimate of the project duration (how long the project will take to finish). In the case of the four paths through the example project, the critical path is the first one, which takes 7.5 hours. The project duration, then, equals 7.5 hours. This assumes that other people can do the taping, plugging, and purchasing for you.
NOTE: The 7.5-hour duration along the critical path assumes that you work alone. If someone helps, you can shorten the task durations. Likewise, the project duration can only be as reasonable as the task durations you enter. So the project can also last much longer, especially if you take the unexpected into account. For example, if your dog knocks over a ladder, the Cleaning task may take several times longer than you expected.
Project management software calculates the durations of each of the paths through a project, identifies the critical path, and gives the project duration. In the simple example project, making the required calculations isn’t much work. You don't need project management software in a sense because you can do the calculations yourself by hand. But when projects include hundreds of tasks and dozens of paths, the time savings that come from using project management software are enormous.
At this point, you may be asking yourself why you would want to go to the effort of estimating durations (even with the help of project management software) so you can calculate the critical path. You will usually want to know your project’s critical path for three reasons.
First, because the duration of the critical path equals the duration of the project, having the project management software identify the critical path lets you estimate when you will finish the project. In the case of the example project, because the critical path equals 7.5 hours, you know that once you start the project, it will take at least 7.5 hours to complete.
Second, by having the project management software identify which tasks are on the critical path, you know which tasks cannot be delayed without delaying the project. For example, the Painting task is on the critical path. If that task takes longer than the estimated 4 hours, your project takes longer than 7.5 hours.
Third, by having your project management software identify which tasks aren’t on the critical path, you know which tasks can be delayed without delaying the project. For example, the Buying task isn’t on the critical path. So, to some extent, the Buying task can be delayed without delaying the project. The amount of time a task can be delayed without delaying the project is called slack. To determine the actual amount of slack, you need to know when a task can start and when a task must finish, which is the subject of the next section.
Using Start and Finish Dates and Times
Start and finish dates and times make up a second aspect of the timing of tasks. Project management software must calculate four dates and times for each task: early start, early finish, late start, and late finish. The early start shows the earliest date or time you can begin work on a task. The early finish shows the earliest date or time you can expect to complete a task. The late start shows the latest date or time you can begin work on a task without delaying the project. The late finish shows the latest date or time you can complete a task without delaying the project.
Does any of this information—knowing when tasks need to be initiated and completed—help? Yes, especially if you have a large number of tasks in a project, because tracking a large number of tasks is more difficult.
The arithmetic for calculating start and finish dates and times isn’t difficult, but it is rather tedious. Thankfully, project management software performs the arithmetic for you.
Identifying and Allocating Project Resources with Project Management Software
The third activity performed by project management software is identifying and allocating the resources you require to complete a project. Typically, you need both people and equipment to complete tasks. And because resources are limited, you usually need to organize your projects with an eye to available resources.
Take, again, the example project of prettying up your apartment. If you add the durations of all the tasks, the project in total requires 10 hours of time from one or more persons. That’s a resource. If you’re tackling the ceilings, the project probably requires ladders or step stools. Those are resources, too.
Because projects usually require resources—both people and equipment—you want to make sure that your plans assume realistic use of any resources. Here are the general actions you take to recognize the resources planned for a project:
1. List the resources you have available.
2. Allocate resources to project tasks.
3. Adjust for any discrepancies between the resources you have available and the resources you need.
In listing the available resources, include both people and equipment. For the example project, for example, your people resources probably include yourself and perhaps a helpful friend. Your equipment resources may include a ladder, paintbrushes, a roller and pan, and drop cloths to protect your furniture and carpet. You can actually create a resources list from this information:
Me
My best friend
A 10-foot ladder
Two paintbrushes
A roller and pan
Two 10-by-16-foot drop cloths
In allocating resources, you commit a resource to a task and, as a result, take it off the list of available resources for the time that you’ve scheduled it. If you allocate your best friend to the task of washing the walls, for example, remove him or her from the resources list. If you allocate the use of the ladder for plugging holes with patching compound, remove the ladder from the resources list.
After you complete the first two steps of recognizing project resources, you use the project management software to resolve any discrepancies between what the project needs and what you actually have available to allocate. Essentially, you use the project management software to verify that neither of the following two error conditions exists:
1. Resource shortages
2. Resource overallocations
Resource shortages refer to situations in which you need a resource for a task, but the resource is not available. If your project calls for you, a single individual, to complete the work within the 7.5-hour project duration, you need more than one person because the project amounts to 10 hours of work.
Resource overallocations refer to situations in which you allocate a resource to different tasks that use the same resource at the same time. If your example apartment project calls for the ladder to be used simultaneously—by you as you plug holes and by your best friend—a resource overallocation exists.
A resource overallocation also occurs when a task requires more time than a resource can provide. For example, if a person works 8 hours a day but a task requires 16 hours a day of work, the person is overallocated.
The project management software process of rescheduling a project’s tasks so that resource overallocations are eliminated is called resource leveling. Resource leveling generally involves stretching out the work on tasks so that resources are used more evenly. If necessary, however, resource leveling can also stretch out the critical path.
In the imaginery project described here, for example, the project’s critical path is 7.5 hours and the project requires 10 hours of work. If you can’t get a friend’s help and therefore end up doing all 10 hours of work yourself, you won’t be able to finish the 10-hour project in a mere 7.5 hours. You’ll be overallocated. Your only recourse—assuming you can’t recruit another friend/resource—would be to stretch out the 10 hours of work over 10 or more hours. In this case, you would be leveling resources.
With only a handful of tasks and a short list of resources, identifying and allocating resources might not be worth the effort. Most projects, however, do benefit from the sort of resource allocation and leveling performed by project management software. Even in relatively small projects, forgetting about a resource or inadvertently overallocating a resource is all too easy.
Monitoring Project Time, Resources, and Costs using Project Management Software
The fourth activity performed by project management software is monitoring the actual time spent on tasks, the actual resources used by tasks, and the actual cost of a project. Traditionally, the project management software monitors these three characteristics—time, resources, and cost—by comparing what you planned with what actually occurs.
Sometimes this business of comparing planned figures with actual figures gives you unfavorable results. Unfortunately, the comparisons made by the project management software often shows that a project is progressing more slowly, is using more resources, and is costing more money than you originally planned. However, the comparisons provide you with an early warning system. And, often, the early warnings give you time to remedy problems when they are little rather than big.
A common project management software technique for monitoring project time, resources, and costs is earned value analysis. Earned value analysis refers to the very logical process of comparing the planned progress and cost of some task with the actual progress and cost. Take the Paint task in the example project. If the project schedule indicates that this task will take 4 hours, starting at 11 A.M. and finishing at 3 P.M., you can use this information to manage the completion of the task. To do so, simply compare the planned work with the actual work to see whether work is progressing at the planned rate. For example, you could verify that task begins at 11 A.M. and verify at periodic intervals that work continues at the planned rate. For example, you could verify at 12 P.M., 1 hour into the planned task, that someone has actually been working for an hour. You could verify at 1 P.M., 2 hours into the task, that someone has actually been working for 2 hours, and so on.
NOTE: Comparing planned work with actual work might be done on the basis of hours as illustrated in the preceding paragraph. Such comparisons can also be performed using cost. In the case of the example project, if you were paying your friend $10 an hour, you could also check to see that you had incurred $10 of labor cost after 1 hour, $20 after 2 hours, and so on.
The comparison of planned work with actual work is often very useful for assessing whether resources are working according to your schedule or plan, but unfortunately, the comparison doesn’t indicate whether your original duration estimates are reasonable.
You can often make another comparison that lets you assess the goodness of your duration estimates, however. You can compare the planned work scheduled in some interval to planned work performed in some interval. Suppose, for the sake of simplicity, that in the imaginary project, you will do four walls but not the ceiling. Further suppose that all four walls are roughly the same amount of work. In this case, you could also say, because the task duration is estimated as 4 hours, that your plan is to do one wall each hour. At 12 P.M., 1 hour into the Painting task, you could verify not only that someone has been working for an hour but that he or she has painted one of the four walls. If the person has been working an hour but hasn’t yet finished a wall, you would know that your original duration estimates were suspect.The key to making comparisons of actual work performed and planned work performed is to have some metric that quantifies the actual work. Often times, project management software plots earned value graphs that visually show planned work scheduled, actual work performed, and planned work performed. What such a graph might show in this case is that the original duration estimate for the task was low but that by applying extra resources the project still finished by 3 P.M.
More information on project management software