Creating a work breakdown structure: the plan of plans in project management

The work breakdown structure (WBS) is also known as the mother of all plans in project management. It provides a structured representation of the content of the entire project. It forms the basis for all other planning steps and plans that are created according to it.

DIN 69901-5:2009-1 "Project management - Project management systems - Part 5: Terms" defines four terms relating to project structure and WBS as follows:

The task of the WBS is therefore only to fully depict the project structure. It is the graphical representation of the project's scope of delivery and services. The WBS is therefore about WHAT needs to be done. It does not provide any information about the time sequence of the individual activities, their duration or even start and finish dates.

The project object is subdivided hierarchically in the work breakdown structure into sub-projects, sub-tasks and work packages. The aim is to structure the project into manageable and delegable units (work packages), on the basis of which effort can be estimated, resources allocated and schedules created in the next step. Unambiguous coding ensures clear identification of the elements.

A work breakdown structure can be expressed up to any level. Three project structure levels are the recommended minimum. The lowest element in a tree structure that is not further subdivided is called a terminal element. In the work breakdown structure, these are usually the work packages.

Work packages describe self-contained and delegable tasks. A work package at task level is a task that:

	can be realistically and reliably estimated.
	makes no practical sense to break down further.
	delivers a result that can be measured.
	could be outsourced or commissioned.

To answer the question, "When is the planning detailed enough?" there are various rules of thumb. The "80-hour rule", for example, states that no activity at the lowest hierarchical level should require more than 80 hours of effort. Another rule is that no activity or group of activities should be planned for longer than a single reporting period. In addition to such rules, common sense and personal experience are of course generally useful.

The work breakdown structure is created during the planning phase of a project. It is therefore part of the project plan, as are the previously carried out target definition, project environment analysis with stakeholder and risk analysis and the communication plan.

The work breakdown structure is ideally created by the project manager during the project planning phase in the form of a workshop involving a well-chosen group of participants. Experience and technical expertise are crucial in order to be able to define all the necessary work packages. In practice, the brainstorming or mind mapping method is suitable for this.

The effort involved in creating a work breakdown structure is worthwhile in many ways:

1. Complete representation ensures a uniform understanding of all project deliveries and services, including project management efforts
2. Determination of all work packages (cost units) belonging to the project
3. Organize and structure the work packages in a suitable system (cost unit structure)
4. Good basis for communication, as it is understandable for all stakeholders
5. Basis for common terminology
6. Basis for delegating and defining responsibilities (e.g. sub-project managers for sub-projects and work package managers)
7. Specification of a structure for all project management tasks (planning, controlling, monitoring)
8. Basis for structuring all project documents (specifications, reports, etc.)
9. Basis for all further plans

In traditional project management, the detailed planning of your project begins with the work breakdown structure.

In practice, the work breakdown structure planning method is often neglected. This may be due to the fact that work breakdown structures are often not implemented as standard in project management software and the focus there is primarily on scheduling using Gantt charts.

In simple projects for which a detailed functional specification already exists, the development of a work breakdown structure may actually be superfluous. However, the prerequisite is that the project content has been recorded in some structured form. However, the creation of a complete work breakdown structure (project or product structure plan), which represents the scope of the project, is mandatory when implementing projects according to PM standards.

In a larger project, the work breakdown structure is essential. It helps to visualize the concrete scope of services and designates responsibilities. In addition, the WBS assigns codes for the various activities. Work breakdown structures are also ideal for presenting the project scope completely and clearly, without immediately mapping the additional complexity levels of time and resource planning. The work breakdown structure offers the ideal opportunity to fully grasp the project content for the first time by breaking down the complex project into more manageable tasks.

The term work breakdown structure is often equated with other terms. Let's take a closer look at the differences!

Project structure and process structure

The project structure, shown in the work breakdown structure, must be clearly distinguished from the flow plan, shown in the flowchart. They are often used almost synonymously, as many project management software products handle both planning steps together in one view or with one functionality. Both planning steps are part of the project planning phase, but project structure planning precedes flow planning. The flowchart, usually presented as a Gantt chart, breaks down the chronological sequence and dependency structure of the activities previously defined in the work breakdown structure.

Work breakdown structure and product breakdown structure

The PRINCE2® project management standard recommends the creation of a work breakdown structure instead of a work breakdown structure. If the work breakdown structure has a consistent object-oriented structure, the product breakdown structure and work breakdown structure can be mapped to each other.

Work breakdown structure and story map

In agile managed projects according to Scrum, the story map corresponds to the work breakdown structure. A story map structures the product backlog according to epics and user stories.

Work breakdown structure and work breakdown structure (WBS)

The work breakdown structure is a planning element defined in the IPMA/GPM standard for project management. The PMBOK® Guide, which defines project management according to PMI, defines the work breakdown structure (WBS) very similarly to the work breakdown structure. However, the WBS focuses on structuring according to work processes and partial results. A deliverable must also be defined for each work package.

If you want to create a work breakdown structure, you should use professional project management software. You can also create informative work breakdown structures in MS Excel, MS PowerPoint or special mind map, diagram or table software. However, comprehensive project management software allows you to record all the necessary information centrally, make changes and additions at any time and at the same time provides the data basis for carrying out the remaining project planning steps directly.

In the "Structure plan" view, the Projektron BCS project management software displays projects in a hierarchical tree structure of project structure elements of any depth. Here you can not only view, edit and filter the structure of your project consisting of sub-projects, work packages, milestones and tasks, but you also have the option of specifying the duration of processing for each task directly for the subsequent process planning. You can define or change the order of the structural elements simply by dragging and dropping.

Use the comprehensive project planning functions of Projektron BCS to automate your planning processes, reduce planning effort and avoid errors - no matter which project management method you use. See for yourself and test Projektron BCS now, free of charge and without obligation.

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The work breakdown structure (WBS) is a key tool in traditional project management for defining the scope of a project and presenting it in a structured manner. It forms the basis for all further planning steps and plans. A well-prepared WBS offers numerous advantages, such as a uniform understanding of the project, a good basis for communication for all stakeholders, the possibility of defining and delegating responsibilities and structuring all project management tasks.

When creating a WBS, there are a few tips to keep in mind, such as including project management tasks as a separate sub-project, avoiding excessive detail, using a consistent coding scheme and adhering to the 100% rule to cover the entire project scope. It is also important to avoid overlap and duplication when defining the scope and to set clear deliverables for individual phases.

Although project structure planning is sometimes neglected in practice, the effort involved in creating a WBS is worthwhile in many respects. It provides a solid basis for planning and controlling a project, promotes a common understanding and supports effective collaboration between all parties involved. Use Projektron BCS to easily create a clear work breakdown structure that supports the success of your project.