INTRODUCTION

The Practice Standard for Scheduling provides the framework to create, manage, and maintain schedules in a project environment. This practice standard contains five main sections. Each section provides additional information on the content and terminology used in this practice standard:

Section 1 — Introduction. This section provides an introduction to scheduling and its benefits, as well as an overview of the development and use of schedule models.

Section 2 — Schedule Model Principles and Concepts. This section provides guidance and information on the principles and concepts associated with schedule model creation and use within predictive, adaptive, or hybrid environments.

Section 3 — Schedule Model Good Practices Overview. This section provides guidance and information on generally accepted good practices associated with the planning, developing, maintaining, communicating, and reporting processes of an effective critical path method (CPM) schedule model approach.

Section 4 — Scheduling Components. This section provides a detailed catalog of the potential components of a CPM scheduling tool.

Section 5 — Conformance Index. This section provides an overview of the conformance index process. It provides a method for assessing how well a CPM schedule model incorporates the components, guidelines, definitions, behaviors, and good practices outlined in this practice standard.

Appendixes contained in this practice standard are:

Appendix X1 — Third Edition Changes

Appendix X2 — Contributors and Reviewers of the Practice Standard for Scheduling – Third Edition

Appendix X3 — Conformance Assessment Scoring Table

Appendix X4 — Conformance Assessment Worksheets

Appendix X5 — Forensic Schedule Analysis

This practice standard includes adaptive approaches such as agile (see Sections 2.2.3 and 2.6). However, the majority of the content of this practice standard, except where indicated, describes a traditional (i.e., predictive) approach to scheduling using CPM. Additional information on agile may be found in the Agile Practice Guide[1].

Section 1 provides an overview of the content of this practice standard and is divided as follows:

1.1 Project Scheduling

1.2 Why Scheduling?

1.3 Overview

1.4 Purpose

1.5 Applicability

1.1 PROJECT SCHEDULING

Project scheduling ensures the development of effective schedule models through the application of skills, tools, techniques, and intuition acquired through knowledge, formal and informal training, and experience. A schedule model rationally organizes and integrates various project components (e.g., activities, resources, and logical relationships) to optimize the information available to the project management team and facilitate the likelihood of a successful project completion within the approved schedule baseline. Key schedule model terms are defined as follows:

[??] Milestone. The PMI Lexicon of Project Management Terms[2] defines a milestone as: A significant point or event in a portfolio, program, or project. For the purposes of this standard, a milestone is a significant point or event in a project defined with a duration of zero time periods.

[??] Activity. The Lexicon[2] defines an activity as: A distinct, scheduled portion of work performed during the course of a project. For the purposes of this standard, an activity is a unique and distinct scheduled portion of work with a duration greater than zero time periods, to be performed during the course of a project.

[??] Resource. A skilled human resource (specific disciplines either individually or in crews or teams), equipment, services, supplies, commodities, materials, budgets, or funds required to accomplish the defined work.

[??] Logical relationship. A dependency between two activities or between an activity and a milestone.

The terms scheduling tool, schedule model, schedule model instance, and schedule presentation are defined in the glossary of this practice standard and described as follows:

[??] Scheduling tool. A tool that provides schedule component names, definitions, structural relationships, formats, and algorithms for schedule calculation that support the application of a scheduling method.

[??] Schedule model. A representation of the plan for executing the project's activities including durations, dependencies, and other planning information, which is used to produce a project schedule along with other scheduling artifacts. The schedule model is dynamic and is developed and maintained by the project team with input from key stakeholders. It applies a selected scheduling approach to a scheduling tool using project-specific data. The schedule model can be processed by a scheduling tool to produce various schedule model instances.

[??] Schedule model instance. A version of the schedule model that has been processed by a scheduling tool based on inputs and adjustments made to the project-specific data within the scheduling tool. The scheduler saves the schedule model instances as project records and for reference, including data date, version (based on a completed update cycle), target schedule models, and the baseline schedule model. The instances can produce various schedule presentations. When used together, the instances support report generation and analysis, such as variance and risk analysis.

[??] Schedule presentation. An output published from a schedule model instance used to communicate project-specific data for reporting, analysis, and decision making. Presentations may include bar charts, critical paths, near critical paths, resource profiles, activity assignments, baselines, record of accomplishments, risks/issues, etc. Presentations can also provide time-based forecasts and identify performance deviations throughout the project's life cycle.

1.2 WHY SCHEDULING?

Projects are complex temporary endeavors; however, a detailed schedule model that contains logically related work allows the project to be simplified into manageable phases or groupings of activities. These phases or groupings allow management to optimize the trade-offs between scope, cost, and schedule. Project performance is reported and monitored when progress against these activities and milestones is recorded within the schedule model. As progress is recorded on a project, the remaining effort, as defined in the approved baseline, requires reassessment. The execution of a project often proceeds differently than the initial plan and baseline. In a typical project...