Project Scheduling: Dynamic Techniques

Dick Billows, PMP
Dick Billows, PMP

Project scheduling is not about developing and printing a schedule and then hanging it on the wall.  Good project managers use their dynamic schedules daily to model options, assess alternatives and forecast completion dates and costs. Here’s how a project manager who is a good scheduler operates:

A stakeholder stops the project manager at the entrance to the cafeteria and says. “Sorry but I have some bad news for you.”

While listening, the project manager flips open his portable PC and opens the project to which this stakeholder is lending people.

The PM asks, “Oh, what’s happened?” while scrolling to a list of the tasks to which this executive’s people are assigned.

The stakeholder replies, “I have to pull those three engineers off your project to work on something the Marketing VP dumped in my lap.  I need them for 4 weeks.”

The PM scrolls down the list, finds the three engineers, changes their availability for the next 4 weeks to zero and clicks enter.  On the screen Gantt chart a lot bars turn red and shift to the right (later finishes). The PM says, “As long as you’re talking to the Marketing VP about removing the three engineers from this projects, you can tell her that her tracking  system will be 6 weeks latter than currently scheduled.”

“Oh no,” the stakeholder moans.

“That’s the consequence,” the PM replies. “I’ll tell engineering and accounting about the delays this causes on their deliverables.  You may hear from them.”

The stakeholder says, “Wait awhile before you do that.  Let me see if there is another way.”

The PM smiles.

Dynamic Project Scheduling Techniques

Dynamic project Scheduling


Successful project managers use dynamic project scheduling because it saves them significant amounts of time. It also lets them quickly model the impact of changes to resources, work or costs. Dynamic scheduling automatically recalculates the duration and budget for the project every time you make a change in the resources, hourly rates, hours of work and predecessor relationships.

Many commercial project scheduling software products allow for dynamic scheduling. Here are the critical elements required for the dynamic schedule to work.

Dynamic Project Scheduling Element #1: Predecessors

Your dynamic project schedule must not be based on fixed start and finish dates. It must be based on predecessor relationships between tasks. There are three primary kinds of predecessor relationships and the entire schedule must be built on these relationships. Predecessor Relationships

  • First is the finish-to-start predecessor relationship between tasks A and B. That tells the software that task B can’t start until task A has finished.
  • Second is the start-to-start predecessor relationship between tasks A and B. That tells the software that tasks A and B can start at the same time.
  • Third is the finish-to-finish predecessor relationship between tasks A and B. That tells the software that tasks A and B must finish at the same time, even though they may not start at the same time.

Dynamic Project Scheduling Element #2: Work Durations

Your schedule must be based on work durations that are calculated from resource availability and work estimates. You enter the amount of work required for a task and the availability of the resource assigned to the task. Availability is how many hours a day each resource can work on their task. As an example, say there is 80 hours of work for a team member who works on the project half-time, or four hours a day. The dynamic project scheduling software calculates the task’s duration as 20 working days. That’s because the half-time team member can only complete four hours of work a day.

Dynamic Project Scheduling Element #3: Track Work & Duration

You use dynamic project scheduling with predecessor relationships and work estimates to track progress on the tasks in your project plan. As an example, you may specify a finish-to-finish predecessor relationship. That tells the project management software that you want to schedule two tasks and their resources so both tasks finish at the same time. When you  specify all your predecessor relationships, your project plan becomes a network of tasks, linked by the predecessor relationships. The result is often called a PERT (Program Evaluation and Review Technique) chart. It displays your project plan and its network of tasks.

You link each task bar to the project network.  That allows our dynamic project scheduling to control the sequencing of tasks based on the predecessor relationships and the amount of work in each task.  It also gives you early warning on problems.  When a task is completed late, the software shows the revised completion date(s) of that task’s successor tasks. You have an opportunity to correct a situation that can impact the entire project’s schedule.

You can learn how to use dynamic project scheduling in our online project management courses.  You work one-to-one with your instructor at your pace and as your schedule allows.

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Author: Dick Billows, PMP

Dick has more than 25 years of project and program management experience throughout the US and overseas. Dick was a partner in the 4th largest professional firm and a VP in a Fortune 200 company. He trained and developed 100's of project managers using his methodology. Dick is the author of 14 books, over 300 articles and director/producer of 90 short project management training videos. He and a team of 25 project managers work with client companies & students across the US and in Europe, South America, Asia and the Middle East. They have assisted over 300 organizations in improving their project performance. Books by Dick Billows, PMP are on