The Conventional WBS

Several useful standards may aid you in developing your WBS. The PMI has a relatively new one [5], and the U.S. DOD has a very comprehensive one [6]. Harold Kerzner provides the following criteria for a WBS [7]:

[T]he project manager must structure the work into small elements that are:

• Manageable, in that specific authority and responsibility can be assigned.

• Independent, or with minimum interfacing with and dependence on other ongoing elements.

• Integratable so that the total package can be seen.

• Measurable, in terms of progress.

A properly prepared WBS should facilitate the following:

• Ensuring better understanding of work;

• Identifying end products and deliverables;

• Defining work in successively greater detail;

• Relating end items to objectives;

• Assigning responsibility for all work;

• Estimating costs and schedules;

• Planning and allocating company resources;

• Integrating scope, schedule, and cost;

• Monitoring cost, schedule, and technical performance;

• Summarizing information for management and reporting, providing traceability to lower levels of detail;

• Controlling changes.

The WBS usually has levels assigned; for example:

Level 1: Total Program

Level 2: Summary Cost Accounts

Level n - l: Work Package

Level n: Activity

In some cases, these words have different meanings. In particular, in many cases the work package is the lowest level of work assignment, restricted to one resource provider per work package.

The WBS also has a numbering system that provides a unique number to every piece of work defined. The numbers usually follow the hierarchy of the levels, with the lowest level corresponding to a charge number for collection of cost.

Project managers use different approaches to subdivide a total project into a WBS. The most preferred is a product-oriented WBS, where each work package produces a definable, measurable output. The collection upwards then may follow functional lines, or, for major pieces of hardware (including facilities), subsystems and systems.

The most important aspect of the WBS is that it be comprehensive. Since it is the basis for all planning and cost estimating, nothing should be left out. In addition, if the project funding decision is going to be based on cost, it is imperative that the WBS not be redundant.

Many companies use templates to create the WBS for similar projects. These can be a useful resource to get started. However, templates share a major shortcoming with other checklists in that they tend to provide a degree of comfort, sometimes stifling thinking beyond the items in the checklist. The project manager has to be vigilant not to allow templates to constrain thinking and to ensure that all required work is covered in the WBS.

Sometimes clients (especially government clients) will dictate a WBS structure, usually because they need to compare projects by different contractors or according to different types of purchases. This is a legitimate client need and must be honored. The project manager still must assure that all project work is covered, that there are no redundancies, and that responsibility assignments are unique and appropriate.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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