Critical Chain Benefits From Traditional PM

Filed under Critical Chain | Posted by PMStudent

Today I was trying to think of ways to integrate some of the methods and benefits of Critical Chain project management into the traditional PM methodology most companies use. I wanted to pick out one element of CC that would potentially yield the most benefit without much, if any, additional overhead to the project manager. Perhaps this has been written of before, but I haven’t come across it. Most of the CC proponents I’ve come across have an all-or-nothing mentality, so they wouldn’t normally write about this kind of hybrid approach. Here’s what I came up with.

Parkinson’s Law

One of the deadliest risks for slipping on schedule is Parkinson’s Law, “Work expands to fill (and often exceed) the time allowed”. I don’t believe that people on the project are lying around doing nothing because they think they have so much time (like a student might). Instead, people may be doing extra analysis and working on some ideas that might yield truly useful features. Having worked as a developer in a project environment, I can say with honesty that my co-workers and I did this a lot. We were well-intentioned, and we did good work. However, I can also safely say that many of the things we worked on didn’t address a specific customer requirement. They were nice little experiments, and developers love experiments.

The difficulty in managing projects is related to finite resources, time, and budget. Effort which addresses stakeholder requirements directly yield the most value, in that they are fulfilling what you promised. Those deliverables should be addressed first and foremost. If you have time left over, then I’d say it might be OK to work on nice little experiments that may add value.

How can you ensure resources are working on the ‘meat’ before they spend time on desert? I don’t suggest micro-management. That is self-defeating, demoralizing to the staff, and time-consuming.

The Method

Instead, let’s inject a critical chain technique into how you manage this project. Estimates on tasks are usually inflated to allow for slack time in the eye of the estimator. Let’s take the CC method of removing slack and creating a buffer, and apply it to only the lower levels, either on individual tasks or series of tasks. Take the scheduled time and chop off the last 20% of it. (I wouldn’t bother with anything less than 40 hours in duration) This is now your deadline, and the time afterwards until the “official” deadline is the management buffer. Keep communication with the team open and honest, let them know what you are doing. Their goal now is to get the task done by the new due date. If they are done by then, they can spend some time doing “Google-ish” creative brainstorming and experimentation. If not, that’s when the project manager becomes more heavily involved than normal, helping to remove roadblocks and provide more resources. Of course, the PM should be doing this all along, but now is the time to redouble your efforts. It’s important to let the team know that if they go over this deadline, it’s not the end of the world. It shouldn’t even be a negative thing. It’s just an early alert system, and everyone should know ahead of time that there’s just as much chance of going over this deadline as their is hitting it on time or early. Keep the critical path in mind with your decisions, you may have to let a non-critical path task slide to address a critical one.

By managing the tasks this way, resources are compelled to knock out the things that lead to a specified deliverable first, and add the most value. It doesn’t require adjusting the official schedules, or introduce paperwork overhead. This is simply a management technique.

As a solo developer or on a team, I think it would be great to “eat our frogs first” and then either start the next task early, or have a few days to brainstorm about what we can do to add even more value. Working with a team for a short time with a blank canvas, you can pool the skills and do some great team building while generating some really creative stuff. You could also do additional testing and debugging, or start looking at the next task early and brainstorm about the best way to go about it. Or, a little of everything. Let the ones who like engineering do things to fix bugs, enhance the documentation, and make it scale better. Let the prototypers do their thing.


  • Understand CC buffer management and the benefits of it (links below)
  • Get your team on board by showing them the WIIFM (what’s in it for me?)
  • Keep the critical path tasks in mind for decision making
  • For tasks 40 hours or longer:
    • Create a CC deadline by chopping off the last 20% of time from a scheduled task
    • The last 20% is now a management buffer
    • Check status at the CC deadline
      • Not complete: Focus support efforts on the task
      • Complete: Start the next task early, or have a “Google day”!

For some background on Critical Chain and it’s benefits, here are some references for you. Specifically, you need to understand why you’re doing this well enough to get your team to believe in it too. This probably won’t work well with totalitarian rule.

The PM Podcast Episode #57
Focused Performance
The Critical Chain Yahoo Group
Critical Chain and the Design Process – MIT
CC whitepaper from Boeing
More case studies
Yet another case study