Published on August 13, 2020
Updated on October 16, 2020
Read time 7 minutes
Work Breakdown Structure in Project Management
If you are starting as a project manager you may have seen WBS or work breakdown structure, and we are sure you wondered what is a work breakdown structure?
A work breakdown structure, although despite what its’ name may suggest involves breaking down deliverables not work.
This simple confusing fact reiterates why you need to understand what is a work breakdown structure.
Therefore, we have curated this guide to clue you in on all that is WBS.
Let’s start with the basics.
What is a Work breakdown structure?
The first thing you need to know about WBS is what is a work breakdown structure?
The Project Management Body of Knowledge (PMBOK) guide, is a set of guidelines and terminology that are accepted as principles within the industry of project management.
The PMBOK has this to say about what is a work breakdown structure:
“A deliverable-oriented hierarchical decomposition of the work to be executed by the project team to accomplish the project objectives and create the required deliverables”
If you are anything like us, you just read that and thought ‘whhaat?!’
So, let’s break it down.
Simply put, a work breakdown structure allows for the definition of the “what” of a project to be clear.
A work breakdown structure clearly outlines all the elements a project needs to accomplish. This is usually done through a graphical display organized with multiple levels.
The purpose of this chart is to clearly define complex activities are broken down into smaller, manageable elements.
Difference between Work Breakdown Structure, Project Plan, and Project Schedule
Before you can completely understand what a work breakdown structure is you need to know what is not a work breakdown structure.
Often times there is confusion as to the difference between a work breakdown structure, a project plan, and a project schedule.
Let’s consider each of these individually to highlight the difference between the three.
1. Work breakdown structure
As discussed WBS discusses the “what” of the project and highlights the deliverables that need to be achieved for project completion.
Work breakdown structure is a deliverable-oriented breakdown of the entire project into smaller elements. The purpose is to organize the team’s work into convenient parts.
The WBS is a hierarchal structure of the scope of the project.
Moreover, the WBS is one single document.
2. Project plan
The project plan on the other hand is a collection of documents.
There are multiple aspects that need to be planned in a project, and this is where the project plan comes into play.
The project plan not only defines the scope of the project but also details other aspects such as how the project will be executed and managed.
Things that need to be included in the project plan include but are not limited to the resources required to achieve the deliverables, scheduling, risk management, etc.
The project plan is the broadest structure out of the three in terms of the level of detail.
3. Project schedule
Project schedules support a project’s planning by providing start dates and deadlines.
The project schedules provide dates for the tasks identified in the work breakdown structure.
The project schedule also identifies dates and deadlines for other elements of the project and provides an entire timeline for the project.
Types of work breakdown structures
Typically, there are three types of work breakdown structures: deliverable-based, responsibility-based, and phase-based. The go-to approach most commonly adopted is usually the deliverable-based approach.
You will be able to differentiate between the three approaches of work breakdown structures by the elements identified in the first level of the hierarchy of the work breakdown structure.
1. Phase-based work breakdown structure
The first level of a phase-based work breakdown structure will be elements that are typical phases of a project.
The second phase will usually be elements that are distinctive deliverables in each of the phases highlighted.
The lower level of both phase-based and deliverable-based work breakdown structures are elements that are deliverables.
For a phase-based work breakdown structure, work associated with different elements will be divided into work unique to the element in the first level of your work breakdown structure.
2. Responsibility-based work breakdown structure
The responsibility-based work breakdown structure defines the project’s elements by the organizational units that will work on the project.
The first level of the structure in a responsibility-based work breakdown structure will be the organization units, the rest of the levels will often follow the same format as the other two work breakdown structures.
3. Deliverable-based work breakdown structure
A work breakdown structure based on the deliverables identifies connections between the project’s deliverables and the scope.
For this guide, we will focus on deliverable-based work breakdown structures since they are the more common choice.
So what are the benefits of creating a work breakdown structure?
You may be thinking what even is the point of a work breakdown structure?
I mean, what with a project plan, a budget plan, project schedule that should be enough planning to have everything down to the ‘t’ right?
Well, not exactly.
A work breakdown structure is an initial step in developing a complete project schedule. A WBS can aid your team in understanding the project’s scope and deliverables at each level that pertains to them.
- Gives guidance: WBS shows the project deliverables and works needed to be done, allowing your team to be guided through what needs to be done in an organized clear manner.
- Keeps focus on project scope: since the WBS is clear and concise, the focus of the document is on the scope and deliverables of the project. This allows your team to stay focused on what is within the scope.
- Helps prevent changes and scope creep: WBS shows the breakdown of the entire project clearly highlighting what is in scope. The diagram allows for the project scope and deliverables to be clear for your team members but also stakeholders.
- Provides easy estimation for resource and time management: WBS is the foundation you can use to create your project budget and schedule. With all the connections between the deliverables and those deliverables needed to complete the project, your job of assigning resources and setting timelines will be much easier.
- Accountability: with a WBS all elements are mutually exclusive. This exclusivity allows accountability to be created. A team allocated to a work package is completely accountable for its completion and success. This allows you to avoid overlap of responsibility.
How do you go about making a work breakdown structure?
There are different ways you could go about creating a work breakdown structure, depending on what will work for you and your team.
However, here is a simple structure and process you can follow to make the task easier for you.
The structure of the work breakdown structure development process will generally follow this outline:
- Work breakdown structure
- Work breakdown structure dictionary
- Scope baseline
1. Understand what is within your project’s scope
Before you can get down to creating your work breakdown structure you need to ask yourself:
What is our project’s scope?
You can do this by first and foremost gathering critical project documents. Namely, the project statement and the project scope management plan.
The project’s scope statement will allow you to recognize the project’s scope clearly and in detail.
The project’s scope management plan will allow you to appreciate how you can deal with changes to your project’s scope, which directly affects your deliverables.
2. Determine your project’s deliverables
The next step of creating a work breakdown structure is identifying the level one elements, in other words highlighting your project’s deliverables.
Ensure that you include all the major deliverables necessary for the successful completion of your project.
When determining the deliverables ensure that each deliverable is essential to the success of your project.
Furthermore, each deliverable you identify should be the responsibility of an independent team in your project.
3. Create work packages
A work package is a deliverable at the lowest level of the work breakdown structure.
You need to decompose, or breakdown your level one deliverables into lower-level deliverables or work packages.
Try and make sure that you identify all the work necessary to complete the deliverable you are decomposing.
Ensure that each work package follows these points:
- Each work package should be independent. The work package should not be dependent on any other element and be mutually exclusive.
- You should have work packages that are definable. Each work package should have a clear beginning and end. These work packages should also be clear and understood by all your team members.
- Your work packages should allow you to estimate resource requirements and timelines.
- Your work package should be manageable.
- Each work package should be able to integrate to create level one elements.
- Ensure that the work packages that you identify are adaptable, to adhere to any changes in your project plan or scope.
Ensure you have broken your deliverables into manageable elements and that there is no need for any additional decomposition.
4. Create a work breakdown structure dictionary
The work breakdown structure dictionary is to explain the definition and scope of each of the elements in your work breakdown structure.
The dictionary is a supporting document that allows teams to easily understand the work breakdown structure.
This document is not a necessity for every work breakdown structure however but does allow for your work breakdown structure to be more accessible and easier to understand.
5. Decide on a format and create your work breakdown structure
After deciding and identifying your work packages and possibly making a work breakdown structure dictionary it is time to decide on the format your work breakdown structure will take.
There are multiple formats you can follow, and whichever you pick is really up to what will benefit you most as a project manager and be easier for your team to understand.
You can create a text-based hierarchal grouping or make a more visual tabular structure.
Once you decide on your format all that’s left is to create the work breakdown structure.
Characteristics of an effective work breakdown structure
Keep in mind that any effective work breakdown structure has these following elements:
- Deliverable-oriented structure of project elements
- Formulated by those doing work on the project
- Includes the complete work defined by the scope, capturing all deliverables in terms of the work that needs to be completed
- Defines the project, describes the work and project scope clearly
- Created in a chart, illustration or outline format
- Arranges deliverables in a hierarchal layout
- Contains at least two levels
- Uses nouns or adjectives, and avoids the use of verbs
- Is adaptable allowing for continual improvement
- Employs a coding scheme for each element that identifies the hierarchal nature of the work breakdown structure when viewed.
There you have it!
And there you go. Here are all the basics you need to understand what a work breakdown structure is.
Now have at it and start creating.
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