Work Breakdown structure

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Work Breakdown structure

Work Breakdown structure
  30 August, 2022   Dr. Preeti Adhav

Work Breakdown Structure, or WBS, is one of the fundamental tools of project management that gauges the scope of a project in a highly structured way. In layman’s terms, the Work Breakdown Structure breaks down a project into products or deliverables in order to facilitate the planning and execution of the said project.


Ofttimes, the projects we undertake are too big and complex to be understood in their totality. While looking at the bigger picture, we might accidentally overlook the smaller elements that make up a colossal project. The lack of proper planning and subsequent confusion may lead to negligence of vital elements, unnecessary overwork, budget deficit, and failure to meet the deadline. This is where the Work Breakdown Structure comes in.


The proper way to plan a project is to develop a Work Breakdown Structure. The primary objective of this is to organise and define the total scope of the project. This enables us to recognise all the necessary tasks, how they have to be performed, the time they will take, and the requisite budget for the execution of the project. By breaking down a large project into smaller components, the Work Breakdown Structure makes the project more manageable by dividing tasks amongst the team members and allowing them to work in tandem, taking the project forward. Like pieces of a puzzle, each task comes together in the end as a whole.


The process of Work Breakdown Structure entails a hierarchical decomposition of a project into products or deliverables and identifying the activities necessary to accomplish the tasks. There are two approaches to a WBS. The first approach is phase-based, where the project is broken down into many phases, each with elements unique to them.


The other approach is the more popular one, but not necessarily the superior one. This type of WBS is deliverable-oriented. It means the project is broken down into deliverables to create a Work Breakdown Structure and then used to identify the tasks that need to be carried out for scheduling and allocating resources. Deliverables are anything tangible, an end product if you will. The scope of a project is comprised of deliverables. In order to avoid any surprise roadblocks, a Work Breakdown Structure has to be planned in a systemic way.


In a Work Breakdown Structure, the components can be diverse. They may include phases, high-level deliverables, interim deliverables, sub-projects, et al, which are further broken down into tasks to be executed. These tasks are accomplished by work packages, which produce the deliverables. At every level, each component is broken down until we end up at the lowest level of the hierarchy with the individual tasks that will be carried out by a person or a team. The task should be coherent and comprehensible to them.


A good WBS principle is MECE- Mutually Exclusive Collectively Exhaustive. The MECE principle is used by project managers to organise tasks and information. "Mutually Exclusive" proposes that each task should be distinct and must fit into one category at a time; there can be no overlapping. "Collectively Exhaustive" suggests that the Work Breakdown Structure must be inclusive of all possible options and address the project in its entirety. Everything we need to do on our project must be covered in our WBS. 


A Work Breakdown Structure is essential for any project of significant scale. There are numerous softwares available for creating a WBS. For a small project, MS Word will suffice. For larger projects, we require some form of project management software that will allow us to capture the entire scope of the project, understand every activity required, assign unique reference numbers against every deliverable, and thus create a roadmap for the teams and individual members to follow.


The preliminary step of producing a Work Breakdown Structure is recognising and numbering principal activities from whence other elements flow. Sub-number every element at every level until we end up with a comprehensive list of every activity that needs to be performed. In this way, we can capture all the tasks that it will take to manage the project.


A Work Breakdown Structure may take multiple forms. A popular one is the "family tree," where the main project branches into many categories. Each level includes a detailed input of each component that makes it easier for the workers to grasp the concept. WBS may also be captured in lists and tabular formats. The latter allows a member or team to navigate between sections and understand the relevance between them.


At the top of the WBS is the product deliverable. It is the sum total of all the deliverables and the main project we have undertaken. Level one organises the principal activities which set up the categories by which we are going to break down our deliverables. Usually, this level lists the main deliverables, but that is not always the case. Sometimes, it may be the stages or phases of projects, workstreams that are thematic in nature, or even geographic sets of divisions from which further divisions flow.


At level two, the major deliverables are outlined. This is where experts identify the major end-deliverables and interim-deliverables. At the next level, we find the components of major deliverables. Not all of these deliverables need to be end-deliverables. There may be some interim-deliverables as well. This decomposition continues until each deliverable is a unique and self-contained element, independent of other deliverables. It is essential that the entire thing is structured into logical hierarchies and sequenced in a logical order.


The Work Breakdown Structure creates work packages that develop the said deliverables. Once the work packages are created, the main deliverables are ready to be decomposed into smaller components that can be accomplished by an individual or a team. They can then be arranged into logical sequences, which allows us to estimate the required time and resources. Additionally, the WBS can be implemented in assessing risks and determining the direction of the project. It is an indispensable tool for the project manager, whose vision governs the project.