Best Practice 10: Maintaining a Baseline Schedule
Key Questions
Is the baseline schedule the basis for measuring performance?
Does a schedule basis document exist? Does the document
describe the general approach to the program?
describe the overall structure of the IMS, including the scope and purpose of projects, staff responsible for each project, the relationship between projects, a WBS dictionary, the status delivery dates for each project, and a list of key hand-off products and their estimated dates?
describe the settings for key options for the scheduling software?
provide an overview of the assumptions and ground rules, including justification for calendars and any lags, constraints, or long activity durations?
Provide an appropriately detailed rationale for the basic approach to estimating key activity durations and justification of the estimating relationship between duration, effort, and assigned resource units?
contain a dictionary of abbreviations, acronyms, and custom fields?
describe the use of resources within the schedule?
describe the critical risks prioritized in a schedule risk analysis as well as schedule contingency?
discuss the derivation of the critical paths and longest path and justify excessive total float?
Are changes to the baseline schedule reviewed and approved according to the schedule change control process?
Is trend analysis performed, such as monitoring start and finish dates, available float, and available schedule contingency?
Key Documentation
The designated baseline schedule.
A description of the schedule change control process.
The current schedule change control log.
The schedule basis document.
Likely Effects If Criteria Are Not Fully Met
Without a formally established baseline schedule to measure performance against, management cannot identify or mitigate the effect of unfavorable performance.
Good documentation helps with analyzing changes in the program schedule and identifying the reasons for variances between estimates and results, thereby contributing to the collection of cost, schedule, and technical data that can be used to support future estimates.
Thorough documentation is essential for validating and defending a baseline schedule. A well-documented schedule can convincingly argue for a schedule’s validity and can help answer decision makers’ and oversight groups’ probing questions. A well-documented schedule is essential if an effective independent review is to ensure that it is reliable.
If changes are not controlled and fully documented, performance cannot be accurately measured against the original plan. Undocumented or unapproved changes will hamper performance measurement and may result in inaccurate variance reporting, inconsistent stakeholder versions of the plan, and unreliable schedule data.
Without a schedule change control process, traceability for all status updates will be unreliable, and there will be no guarantee that stakeholders are using the same version of the schedule.
Unless schedule variances are monitored, management will not be able to reliably determine whether forecasted completion dates differ from the planned dates.
Without trend analysis, management will lack valuable information about how a program is performing. Knowing what has caused problems in the past can help determine whether they will continue in the future.