Project Scheduling

August, 2015

Key Concept Explanation

As much as in any transformation system, in project-based work, time is a critical production factor. Proper timing is of the essence in meeting the delivery date promised to a customer, as well as in bringing a new product or service to launch. Therefore, it is not surprising to find that the discipline of project management devotes a significant amount of attention to the concepts and tools needed to manage project schedules.

My interest in this topic is a matter of academic curiosity as well as of potential professional relevance. I have come to realize that my work entails a combination of routine duties and projects that often extend over the course of weeks or months. Since my time is a finite resource, I want to learn about tools and techniques that will help me to manage it effectively and make me as productive as possible.

According to Houston (2014), aspects of managing time in a project entail defining constituent activities, determining the sequence in which they should occur, estimating the amount of time that each will take, and developing the schedule. Once project implementation has begun, the schedule has to be controlled; this is a process that involves iterative adjustment to realities that diverge from the plan. Various scheduling techniques and tools are available, including the Gantt chart, critical path method (CPM), and Goldratt’s critical chain. Software, such as Microsoft Project, is available to facilitate schedule management.


Meredith and Shafer’s (2013) Operations Management for MBAs provides a rather straightforward introduction to the techniques of project scheduling. Their overview of the subject clearly establishes that Program Evaluation and Review Technique (PERT) and CPM are two essential tools, and that both bear a relation to the Gantt chart. Their coverage of project scheduling, extending over a total of 14 pages, consists mostly of an explanation of procedures. This is not an uncommon approach. In fact, three of the five sources cited in this thread’s annotated bibliography (Jones, 2011; Lewis, 2011; Dauber, Shim, & Siegel, 2012) follow much the same logic: these are the essential tools, and this is how they work.

Certainly, there is nothing wrong with the functional approach. The manager who does not know how to use the tools cannot benefit from them. Nevertheless, the other two sources in the annotated bibliography (Geraldi & Lechter, 2012; Frese & Sauter, 2014) provide very different insights into project scheduling, equipping the manager to make more judicious choices in pursuit of successful projects. As explained in greater detail below, Geraldi and Lechter produce evidence that suggests that the Gantt chart, while ubiquitous in project management, is based on assumptions that do not cohere with every project, and thus should be used more critically. Frese and Sauter, for their part, address scheduling techniques only tangentially, choosing instead to emphasize that the success of all project management techniques ultimately hinges on effective human communication. These two sources thus provide a context for using the tools whose technical specifications are set forth by the more functionally oriented sources.

Article Summary

According to Geraldi and Lechter (2012), the Gantt chart was developed during the production challenges associated with World War I and has become “a classic tool of project management” (p. 578). Even when scheduling innovations such as PERT and CPM emerged in the 1950s, they did not displace the Gantt chart. Project management software has since ratified the Gantt chart’s prominent place in the project manager’s suite of tools. With this backdrop, Geraldi and Lechter undertook the improbable task of questioning the Gantt chart’s universal utility. From this reader’s perspective, following their analysis first felt a little unorthodox—something as unnatural as second-guessing the balance sheet, the organizational chart, the stock ticker, or the Likert-scale survey question.

Geraldi and Lechter (2012) examined the circumstances under which the Gantt chart originated, finding that it was clearly founded on the assumptions of Scientific Management. Henry Gantt, the luminary whose name the chart bears, “was, as much as [Frederick Winslow] Taylor, concerned with the efficient and effective use of resources and increase of productivity in repetitive, routine operations” (p. 580). The Gantt chart tacitly sets forth six principles concerning work—namely, that it is “time-focused, objective, deterministic, analytic, accountable and sequential” (p. 582). The problem, according to Geraldi and Lechter, is that research over the past century has led toward a much more nuanced understanding of the nature of work and the ways that it can be managed. They proposed, therefore, that using the Gantt chart is justified when a project consists of tasks that can be defined, sequenced, and analyzed in advance. On the other hand, when the outworking of a project is less predictable, a more contextual and reflective use of tools—supplementing the Gantt chart with other visualizations—is in order.


Projects are found in every sector. While they may be most prominent in certain industries, they can occur almost anywhere and involve stakeholders in a broad spectrum of occupations. Managers in general need to understand the basics of project management, if only to apply them informally. Projects entail significant time considerations, justifying the development of various schedule management tools over the past century. Effective managers need to select and use these tools judiciously. This entails a balance of technical competence (grasping how relevant tools work), critical thinking (matching tools to the nature of the work), and interpersonal skill (communicating effectively with project stakeholders). Additionally, believers can face the contingencies of project management with full confidence in God’s sovereign plan.

Annotated Bibliography

Dauber, N. A., Shim, J. K., & Siegel, J. G. (2012). The complete CPA reference. Hoboken, NJ: Wiley. Retrieved from

Dauber et al. (2012) have produced a manual that accounting professionals rely on for guidance in financial, statistical, legal, and professional/ethical matters. The portion of the work discussed here is a section of chapter 9, “Quantitative Applications and Modeling in Accounting,” that addresses PERT. It may seem surprising to find that an accountant’s manual covers a project management technique. Nevertheless, as the authors noted, accountants not only manage projects directly (e.g., master budget development), but also have a significant stake in large-scale organizational projects (e.g., building construction).

According to Dauber et al. (2012), PERT’s main utility is estimating when a project is most likely to be completed, and how likely it is to be completed by a given time. PERT is applied in conjunction with CPM, as it is essential to know which sequence of activities constitutes the longest path leading to project completion. An additional connection between PERT and CPM arises if additional resources are needed to speed the pace of the project. CPM is invoked to determine “which activities must be accelerated in order to reduce the total project completion time” (p. 416).

Frese, R., & Sauter, V. (2014). Improving your odds for software project success. IEEE Engineering Management Review, 42(4), 125–131. doi:10.1109/EMR.2014.6966952

Frese and Sauter (2014) did not report on original research; rather, they summarized key insights from more than 25 years of project management literature. The authors’ primary concern was to elucidate and remedy the factors that can hinder a project’s successful completion. While the context of their article was software development, the principles that they discussed are presumably equally applicable to projects in any other field. The critical reality that they faced was that a majority of IT projects were compromised in some way, leading either to defective completion or outright abandonment.

Essential insights conveyed by Frese and Sauter (2014) included the following:

  • User engagement is a consistent attribute of successful projects.
  • Three factors are common to successful project processes: “good planning, clear responsibility and accountability, and schedule control” (p. 126; emphasis added).
  • Effective communication is at the heart of successful project management. Management techniques are necessarily mediated by “active, frequent and honest communication” (p. 129).

Geraldi, J., & Lechter, T. (2012). Gantt charts revisited: A critical analysis of its roots and implications to the management of projects today. International Journal of Managing Projects in Business, 5(4), 578–594. doi:10.1108/17538371211268889

Geraldi and Lechter (2012) assessed whether the Gantt chart was as suitable to project management as contemporary practice implied. In order to accomplish this assessment, they investigated the conditions under which the Gantt chart emerged nearly a century before: the search for efficient routines in repetitive work—in short, the Scientific Management movement. Having distilled six assumptions about tasks that are arguably embedded in the Gantt chart, they reasoned that these assumptions do not hold true for many projects. Ultimately, they argued that Gantt charts should not be used uncritically, but rather contextually and reflectively. Project managers need to be flexible enough to recognize when the assumptions that underlie the Gantt chart are incongruous with reality, and supplement it with “alternate visual representations” (p. 589).

Jones, A. K. (2011). Critical path method. In W. D. Folsom (Ed.), Encyclopedia of American business (Rev. ed, Vol. 1, pp. 183–185). New York: Facts on File. Retrieved from

Jones (2011) authored a brief introduction to CPM. Coverage included the following:

  • the origin of CPM
  • the significance of the critical path
  • procedures for executing CPM
  • the relation of CPM to PERT
  • managerial insights to be gained from CPM and PERT
  • conditions that justify the use of CPM and PERT

Jones explained one concept—crash time—that other sources cited in this thread failed to cover: “The crash time is the shortest time it would take to finish an activity if more money and other resources where [sic] added to complete the project” (p. 184).

Lewis, J. P. (2011). Project planning scheduling & control: The ultimate hands-on guide to bringing projects in on time and on budget (5th ed.). New York: McGraw-Hill. Retrieved from

Lewis’s (2011) text is an approachable introduction to project management, covering topics such as project definition, planning, execution, and control. The portion of the book analyzed here is the appendix (pp. 515–537), entitled “Schedule Computations.” The author takes the reader step by step through the process of conducting critical path analysis by constructing an activity-on-node (AON) network. Coverage includes (a) rules pertaining to network function, (b) forward- and backward-pass computations, (c) identification of the critical path, (d) explanation of the concept of float, and (e) recommendations for compressing a project schedule. The final pages of the appendix address the limitations of CPM. This is accomplished by contrasting CPM with the bar (Gantt) chart and then discussing aspects of project execution that are not visualized well in CPM.


Houston, V. (2014). Time management in practice. In P. C. Dinsmore & J. Cabanis-Brewin (Eds.), The AMA handbook of project management (4th ed.). New York: American Management Association. Retrieved from

Meredith, J. R., & Shafer, S. M. (2013). Operations management for MBAs (5th ed.). Hoboken, NJ: Wiley.

Want to learn more about project scheduling and related topics?

Click the buttons below to see relevant entries in my bibliography, SmithFile.