What’s the Difference Between Project Life Cycle and Project Phase?

There’s also something that I really like about the PMP exam: it isn’t tricky! The sheer volume of information in the PMP exam, however, sometimes obscures its trickiness. Some — but not all — of the terms in the PMBOK Guide can be defined just by reading them. (If you are well along in your studying, you might know this because every time you read something like “Plan Risk Management”, you already know what’s next.)

Project Life Cycle and Project Phase are two terms that you can’t just guess about. In fact, I’m writing a whole article on both of them because I found that I didn’t really know how to define either very well about a week before I took the PMP exam. I hope I’m getting extra points for my brutal honesty.

Project Life Cycle

PMBOK defines project life cycle as “the series of phases that a project passes through from its initiation to its closure” (38). Aha! Remember that a project life cycle is made up of a number of phases.

There are four key parts that any project generally follows, known in the PMBOK Guide as the generic project life cycle:

  • Starting
  • Organizing and preparing
  • Carrying out the work
  • Closing

Take a look at this graph — know it, love it, dream about it. You’ll probably see it or something like it on the PMP exam:

What's the Difference Between Project Life Cycle and Project Phase?

Intuitively, this graph makes sense, right? Cost and staffing levels increase until and throughout the project team carrying out the work, and the most time is spent on carrying out the work as well.

Another key point from this graph (and in Figure 2-9 in the PMBOK Guide) is that over time, risk and uncertainty decreases, but the cost of changes increases.

Project Phases

Now that you know the generic project life cycle is made up of phases, what are phases? PMBOK calls them “a collection of logically related project activities that culminates in the completion of one or more deliverables” (41). How do you know if you have a phase? Check if it meets the following criteria:

  1. They have a different focus than any other phase.
  2. Accomplishing the work of the phase is different than any other, and it requires Initiation, Planning, Executing, Monitoring & Controlling, and Closing processes that are distinct.
  3. The phase ends with a deliverable that is either moved into the next phase or project closure

Projects may have one or multiple phases, and there are two types of phase-to-phase relationships. Sequential phases are back-to-back, and they produce a longer schedule but less uncertainty. Overlapping phases overlap (duh! This is when you don’t need a definition from the PMBOK Guide), which makes the uncertainty and risk greater, which in turn may cause possible rework.

Project Life Cycles Again

Let’s go back to life cycles for a moment, because we reviewed the generic life cycle, but the PMBOK Guide also gets into more detail on more specific types of project life cycles. Of course you should read the PMBOK Guide starting on page 44, but here’s a brief overview.

  • Predictive / fully plan-driven – scope, time, & cost determined as early as possible but may still use rolling wave planning
  • Iterative and incremental – repeat project activities to achieve result – especially useful if the output is unknown – could have sequential or overlapping phases
  • Adaptive / change-driven / agile – responsive to big changes, with few advance scope definitions and in order to respond to stakeholder input

Let’s put these in context with some examples:

  • Predictive / fully plan-driven – Use this method when the deliverable is understood, such as a when a large company like Proctor & Gamble wants to create a new, state-of-the-art Q-tip
  • Iterative and incremental – Use this method when the deliverable is somewhat understood but requires multiple iterations of a step before moving on, such as the development of a new software by a company like Oracle.
  • Adaptive / change-driven / agile – Use this method for a project that needs quick reaction for the involvement of multiple stakeholders, such as development of something completely new with no prior experience. A startup or innovative company would be likely to use this methodology. In 2017, you’re much more likely to see agile methods used, so the PMP exam focuses more heavily on this topic than it has in the past.

Putting It All Together

Whew! That’s a lot of information, so I definitely understand if you skimmed a bit. When studying for the PMP exam, it is important to read the PMBOK guide multiple times for that exact reason. Take away a few key ideas from this article, and then save it for later review when you need a refresher.

  • The project life cycle is the entirety of the project from start to finish, and it is made up of phases.
  • Project may have one or many phases that are distinguished by different work that occurs in each phase.
  • Projects may be predictive, iterative, or agile based on the characteristics of what is being produced.

Studying for the PMP exam can feel tedious at times, especially when you need to figure out the minute details of project life cycle and project phase as just one bit of information in the mountain of information you need to know for the exam. But if you’re really excited about becoming a PMP, it is also exciting! Making connections throughout the PMBOK Guide that can really help your project can feel like you are going to make a real difference in organization.

So how are you feeling about project life cycles and project phases? Comment with your questions below, and let’s get ‘em answered.

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  • Rich Rinaldi

    Rich writes about Excel and the PMP for Magoosh. He's an Excel nerd who passed his PMP exam with 4 Proficients & 1 Moderately Proficient (curse that Initiation domain!). He earned his BSBA in Operations Management at Georgetown University and his MBA in Non-Profit Management at Chaminade University in Honolulu. He works as a business analyst & project manager at a nationwide non-profit headquartered in Villanova, PA. Rich and his fiancée Hadley enjoy traveling the world or playing with Bear, Cherokee, and Nalani (their cats).