Work Breakdown Structures

The Foundation for Project Management Excellence

Eric S. Norman, Shelly A. Brotherton, Robert T. Fried

• Publisher: Wiley
• Year: 2010
• Print ISBN: 9780470177129
• eBook ISBN: 9781118000267
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Industrial Engineering
• Index: Technology & Engineering

Understand and apply new concepts regarding Work Breakdown Structures

The Work Breakdown Structure (WBS) has emerged as a foundational concept and tool in Project Management. It is an enabler that ensures clear definition and communication of project scope while performing a critical role as a monitoring and controlling tool. Created by the three experts who led the development of PMI®'s Practice Standard for Work Breakdown Structures, Second Edition, this much-needed text expands on what the standard covers and describes how to go about successfully implementing the WBS within the project life cycle, from initiation and planning through project closeout.

Filling the gap in the literature on the WBS, Work Breakdown Structures: The Foundation for Project Management Excellence gives the reader an understanding of:

• The background and key concepts of the WBS
• WBS core characteristics, decomposition, representations, and tools
• Project initiation and the WBS, including contracts, agreements, and Statements of Work (SOW)
• Deliverable-based and activity-based management
• Using the WBS as a basis for procurement and financial planning
• Quality, risk, resource, and communication planning with the WBS
• The WBS in the executing, monitoring, and controlling phases
• New concepts regarding the representation of project and program scope
• Verifying project closeout with the WBS

Using a real-life project as an example throughout the book, the authors show how the WBS first serves to document and collect information during the initiating and planning phases of a project. Then, during the executing phase, the authors demonstrate how the WBS transitions to an active role of project decision-support, serving as a reference and a source for control and measurement.

(PMI is a registered mark of Project Management Institute, Inc.)

Part I

Introduction To WBS Concepts

Chapter 1

Background and Key Concepts

“If you don’t know where you’re going, any road will take you there”

Anon

CHAPTER OVERVIEW

This chapter is placed up front not only because it is Chapter 1, but also because we wanted to provide background information for you before beginning the process of developing Work Breakdown Structures. This chapter introduces key concepts about the WBS that are discussed in much more detail later in the book, along with historic information about the emergence and evolution of the WBS over a number of decades. We also introduce the House metaphor.

The house what? The House metaphor. For our purposes, we will use the term metaphor here to mean a symbol or example that will represent how this concept can be applied in practice — although the example itself is fictitious. Actually, the House metaphor is a tool or rather, a section of a WBS from the construction of a house that we have developed for use throughout the book to help us illustrate our intended meaning — when words alone aren’t enough to clarify and communicate key points or concepts. Following is an outline view of the House metaphor we will use, in one form or another, throughout the remainder of the text.

This metaphor is an important tool to cover at the beginning of the book because we will use it to describe, discuss and illuminate concepts throughout the text. We will use the House metaphor to illustrate examples, to provide a common, practical application of a topic or concept, and as a starting point for detailed examination of related topics.

Exhibit 1.1 House Metaphor — Outline Example

At the highest level, this chapter will contain the following:

• A general description of the Work Breakdown Structure and its role in project management

• WBS background and history

• Key terms and definitions

• The House Metaphor

WORK BREAKDOWN STRUCTURES

Let us begin . . .

Work Breakdown Structures were first used by the U.S. Department of Defense for the development of missile systems as far back as the mid-1960s, and they have been a fundamental component of the Project Management lexicon for nearly as long. The concept of the WBS and the practices around its use were initially developed by the U.S. Department of Defense (DoD) and National Aeronautics and Space Administration (NASA) for the purpose of planning and controlling large acquisition projects whose objective was development and delivery of weapons or space systems (Cleland, Air University Review, 1964, p. 14). These projects often involved many industrial contractors each with responsibility for separate components of the system and were managed by a central administrative office, either within a governmental agency or within one of the contracting firms which served as prime contractor. In this environment, the WBS was used to “ . . . ensure that the total project is fully planned and that all derivative plans contribute directly to the desired objectives” (NASA, 1962).

The point is, that if true, and we assert right here that the statement is true, then the statement raises a question: “If the WBS is a fundamental building block for most projects, most of the time, then why are there so many conflicting viewpoints and approaches to development and use of Work Breakdown Structures?”

The answer to that question is somewhat elusive, and is one of the driving factors for writing this book. In the sections and chapters that follow we will examine various approaches to WBS development and will present a number of concepts, attributes, challenges and ultimately, recommendations for your consideration and use.

DEFINING WORK BREAKDOWN STRUCTURES

The PMBOK^® Guide — Third Edition, defines a Work Breakdown Structure as “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. It organizes and defines the total scope of the project. Each descending level represents an increasingly detailed definition of the project work.” The WBS is decomposed into Work Packages. Work Packages are defined in two different ways in the PMBOK^® Guide — Third Edition. In the text, Work Packages are said to be the “lowest level in the WBS, and is the point at which the cost and schedule can be reliably estimated. The level of detail for Work Packages will vary with the size and complexity of the project. The deliverable orientation of the hierarchy includes both internal and external deliverables” (PMBOK^® Guide — Third Edition, pp. 112, 114). Later in this chapter we provide the Work Package glossary definition for you.

There are a number of important concepts presented in this definition for the WBS. Of particular interest is the concept of deliverable orientation. The inclusion of these words is a key change from the definitions for the WBS in earlier editions of the PMBOK^® Guide and reflects the expanded role the WBS performs in projects today. These changes are highlighted in Table 1.1.

Today, the WBS is understood to be more than an organization of the work of the project. The current definition, with the inclusion of the deliverable orientation wording, indicates that the process of developing the WBS includes the definition and articulation of specific outcomes of the project-the end products and results. By doing so, it becomes a reference point for all future project activities.

Table 1.1 WBS Definition — Changes by Version

(Sources: Project Management Institute, The Project Management Body of Knowledge (PMBOK^®). PMI. Newtown Square: PA. 1987.; Project Management Institute, A Guide to the Project Management Body of Knowledge (PMBOK^® Guide). PMI. Newtown Square: PA. 1996.; Project Management Institute, A Guide to the Project Management Body of Knowledge (PMBOK^® Guide — Second Edition) PMI. Newtown Square: PA. 2000.; Project Management Institute, A Guide to the Project Management Body of Knowledge (PMBOK^® Guide — Third Edition) PMI. Newtown Square: PA. 2004.)

This critically important concept will be expanded later in the book, but we want to point to this definition as a departure point for our writing as well as a point of reference for you. Deliverable orientation is one of the Core Characteristics for the WBS, which we will discuss in Chapter 2. It is a fundamental attribute that will allow your WBS to be more than “shelfware” for your project, and will enable it to perform a critical role as a baseline document for communication of scope and outcomes during the initial phases of your project. In later phases, the WBS performs an active role as a basis for other key executing and monitoring and controlling activities. With these thoughts in mind, we can now take a broader look across the project management horizon to examine current trends and to establish context for our discussion.

There are additional reasons for preferring a deliverable orientation for WBS construction over task/activity or process orientations. With process and task-oriented Work Breakdown Structures, the deliverables or outcomes described by the WBS are the project processes themselves, rather than the project’s products or outcomes. When this is the case, the project team spends a great deal of energy on refinement and execution of the project’s processes, which can ultimately become models of care and efficiency-but that do not necessarily produce the desired outcomes for the project because the focus has been on the process of producing outcomes, not the outcomes themselves.

Additionally, task/activity WBS construction is truly a contradictory concept from the outset. As we will examine later, tasks and activities are truly part of the project scheduling process and have no place in the WBS to begin with. Later, in Chapter 7, we will discuss the creation of the Project Schedule and will explain that tasks, activities and milestones are outcomes of the decomposition of the WBS that extends beyond the Work Package level, (the lowest level of decomposition of the WBS) and yields elements that are carried forward into the project schedule. So from our perspective, developing a WBS based around tasks and activities is simply a contradiction in terms. To us, and to those who wish to develop high-quality Work Breakdown Structures that focus attention on outcomes and deliverables, this truly cannot be useful.

IMPORTANCE OF THE WBS

Everyday practice is revealing with increasing regularity that creation of a WBS to define the scope of the project will help ensure delivery of the project’s objectives and outcomes. There are numerous writings that point to the WBS as the beginning step for defining the project and insist that the more clearly the scope of the project is articulated before the actual work begins, the more likely the success of the project. Here are a few examples from recognized, reliable Project Management sources:

• John L. Homer and Paul D. Gunn “The intelligent structure of work breakdowns is a precursor to effective project management.” (Homer and Gunn, 1995, p. 84).

• Dr. Harold Kerzner: “The WBS provides the framework on which costs, time, and schedule/performance can be compared against the budget for each level of the WBS” (Kerzner 1997, p. 791).

• Carl L. Pritchard: “The WBS serves as the framework for project plan development. Much like the frame of a house, it supports all basic components as they are developed and built” (Pritchard 1998, p. 2).

• Dr. Gregory T. Haugan: “The WBS is the key tool used to assist the project manager in defining the work to be performed to meet the objectives of a project” (Haugan, 2002, p. 15).

• The PMBOK^® Guide — Third Edition stresses the importance of the WBS in the Planning Process Group, which begins with three essential steps — Scope Planning (3.2.2.2), Scope Definition (3.2.2.3) and Work Breakdown Structure Development (3.2.2.4). (PMBOK^® Guide — Third Edition).

Experienced Project Managers know there are many things that can go wrong in projects regardless of how successfully they plan and execute their work. Component or full-project failures, when they do occur, can often be traced to a poorly developed or nonexistent WBS.

A poorly constructed WBS can result in negative project outcomes including ongoing, repeated project re-plans and extensions, unclear work assignments for project participants, scope creep, and...

Table of contents

• Title Page
• Copyright Page
• Preface
• Foreword
• Part I - Introduction To WBS Concepts
• Part II - WBS Application In Projects
• Part III - WBS For Project Management Decomposition
• Appendix A - Project Charter Example
• Appendix B - Project Scope Statement Example
• Appendix C - Project Management WBS Examples
• Appendix D - Answers to Chapter Questions
• Index