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Chapter 8 – The creation of the work breakdown structure (WBS)

Part 3


Technical term Definition
Work breakdown structure Smallest unit in a WBS which describes the activities to accomplish a certain task
Ideally defined as a closed-end performance element, deviating from another and linked to other WPs in a clear and straightforward way
WBS orientations Phase-oriented
Mixture of all three
Work package (WP) Smallest unit in a WBS which describes the activities to accomlish a certain task
Beside these activities, an estimation of the duration and the costs are written down
It's assigned to least one work package manager
Sub-task (ST) A project task that is sub-divided into smaller units in the work breakdown structure
Group of related WPs in the WBS
Subtasks can be defined at several levels, whereby each higher-level sub-task comprises a group of related sub-tasks at the next lower level
Work package owner (WPO) Responsible for the WP
Reports to project management on progress
In charge for preparing a detailed work package description (e.g. activities that must be performed for realisation)
Work package description A detailed document with all relevant information about the work package (e.g. person responsible, WP content, dates, breakdown of activities/tasks)
Coding Classification system for the elements in the WBS
In accordance with the requirements of the organisation's accounting department
Often numerically coded

Let's practice – transfer project

Now it's your turn.

Think of your wedding-project and how you can implement a work breakdown structure.


You won't need a WBS here!
Since there are no overlaps, nor time and cost-expensive phases, the phase model is sufficient. Even though the idea sounds so uncomplicated, sometimes keeping it simple is the best option.

Test yourself!

Now it's time to check your knowledge.

Answer the following questions for yourself. Please take your time and think carefully about what you would answer before revealing the solution.

What is a WBS used for?
  • The WBS is used to break down a project into work units and tasks
  • Cart or table showing project structure
  • Answers the question: "What work does our project involve?"
  • The WBS is a key tool for classification and communication in the project
How can a WBS be broken down? Structuring
  • in terms of the product to be produced (object orientation).
  • in terms of the necessary project function, i.e. functional organisation units (function orientation).
  • in terms of project phases (phase orientation).
  • in terms of a combination of all three of the above (mixed orientation).
Why should you prepare a WBS before the time schedule?

Because there are some sub-tasks and work packages which aren't included in the time schedule but still consume resources (e.g. deadline and cost monitoring). So that you don't forget any important sub-tasks.

What advantages can be gained from using standard work breakdown structures?
Work breakdown structures
  • guarantee some degree of consistency in project planning,
  • save team members the time and effort of having to prepare an entirely new WBS for every new project,
  • act as a checklist and ensure that important items and work packages are not forgotten, and
  • reduce the time and expense involved in planning, thereby contributing to more cost-effective project management.
What rules for creating work breakdown structures have proven to be useful?
  • A work package should, if possible, be defined as a closed-end performance element that is differentiated from and linked to other work packages in a clear and straightforward way.
  • Only one person should be accorded responsibility for each work package – irrespective of how many people will be working on it.
  • When the WBS is phase-oriented, it should be possible to assign each work package to one specific phase. Exceptions are multi-phase tasks, such as the on-going monitoring of costs.
  • Tasks that are outsourced should be designated as independent work packages.
  • A clear specification should be formulated for each element of the WBS so that third parties can easily see whether the work package has already been carried out.
What minimum content should the work package description include?
  • Name, number, version and status (planned, tested, released) of the work package
  • Brief description of content
  • Projected results to be achieved
  • Individual activities involved in the work package
  • Prerequisites for performance (e.g. external supplies required)
  • Projected commencement and completion dates or projected duration
  • Projected costs (generally unit costs, e.g. person days)
  • Work package manager
  • Further information e.g. regulations that have to be observed
What role does a work breakdown structure play in cost budgeting?

Since it charts the components of a project, a work breakdown structure is an essential prerequisite for the application of practically all cost budgeting methods.