Organisational Breakdown Structure - defining the owners of work packages...
An Organisational Breakdown Structure, OBS, complements the Work Breakdown Structure and Resource Breakdown Structure for your project. Its main intent is to communicate how those tasked with delivering the project will be organised and structured as a Project Team. It's without a doubt the simplest of the three structures in terms of understanding, yet performs a great role of communicating the hierarchy of the team and consequently the reporting lines within a project.
The more observant will see how closely it can resemble the 'people' element of the Resource Breakdown Structure , but also the other organisations needed to deliver aspects of the project.

TIP! An OBS is also a good communication tool, nodes could include contact details for those Groups and personnel identified, in essence acting as a Project Specific Contact Directory for all to use.

As can be seen from the diagram above the OBS has a typical tree structure which inherently displays the organisational hierarchy and reporting structure.

In addition to the functions, as shown, the next obvious step is to put names in the frames for each node. A node in the tree denotes groups and sub-groups within the project organisation, names at a group or sub-group level could identify the persons responsible for leading that group within the team.

Each element (node) of the Organisational Breakdown Structure is assigned a unique code. Furthermore, by using a hierarchical coding structure, members of the organisation can be logically associated with Groups and Sub-Groups within the wider Project Team.

Ultimately, there is no reason why an Organisational Breakdown Structure cannot be developed to a level of detail where all individuals within the project are represented. It's a good way to show team members where they reside within the Project Team. A project organisation chart!?

The closer to the top of the OBS, the more likely the nodes will reflect organisations and not individuals, though it's a good idea to identify the responsible lead person within each organisation.

Work Package Responsibility


Each work package and group of deliverables identified by the Work Breakdown Structure will not get completed by itself. They therefore need to be assigned to the area of the Project Team which will be assuming ownership and responsibility for each work package's development and completion.

The commonly adopted approach for this is to assign an Organisational Breakdown Structure code to each of the project's work packages. This code would be taken from the hierarchical structuring code used to identify nodes within the OBS, as noted above.

Since a project work package may be broken down into the activities required to complete the work package deliverables, each activity can also be assigned an OBS code denoting who is responsible for the activity.

This may appear a bit anal, but when dealing with large projects with hundreds of activities in the time schedule, using an OBS code allows the project schedulers to structure reports by OBS, allowing efficient communication of specific scheduling information to only those who need to know.

This becomes more important when you have Groups or individuals responsible for aspects of more than one project at any point in time; they are more inclined to only want to know details regarding their direct responsibilities.

"Feeding the Need! - turning everything on its head."
A traditional Organisational Breakdown Structure resembles the hierarchical tree diagram structure commonly adopted for organisation charts, with those individuals responsible for delivering the detail found generally at the lowest levels of the tree.

I prefer to turn this traditional concept on its head!

Those tasked with delivering the detail arguably have the most important job on the project. If detail is overlooked, contains errors, or is late for whatever reason, the knock-on consequences affecting the remainder of the project can be disrupting at the least, catastrophic at the most.

Does it not make perfect sense then, that those tasked with getting the detail right should be fully supported in delivering their project tasks as effectively and efficiently as possible?

I therefore prefer to turn the traditional way of considering the OBS on its head.

The Organisational Breakdown Structure should therefore resemble an inverted triangle in general shape. Those with the most important roles in delivering the detail of the project then appear at the top of the triangle.

The most important role Project Team members lower down the structure have; is one of supporting and enabling those above them in the Organisational Breakdown Structure to deliver their tasks effectively and efficiently in line with the objectives of the Project.


This requirement of FEEDING THE NEED of those "above" you in the Project Team is relevant to all levels of the OBS, all the way to the Project Manager, Project Director, and also the Stakeholder Organisation.

Unfortunately, all too often projects are structured and organised in the less efficient, authoritarian and less motivated traditional structure associated with a corporate organisation chart.

Organisational Breakdown Structures are a good way of organising and communicating the overall structure of the Project Team.

When coded effectively, the OBS can be combined with the WBS to communicate who is responsible for which work package or group of deliverables.

A combination of WBS code and OBS code can also be used to identify project budget areas (cost centres), which then get fully costed once resources are assigned from the Resource Breakdown Structure .

This then, can become the basis for controlling project cost as well.

To get the best from the Project Team, it is the responsibility of project management to support and enable those tasked with delivering to do so as effectively as possible.