HKSM

The schedule baseline is the approved, time-phased plan for the project's activities, milestones, and key dates. It is the fixed reference used to measure schedule performance, manage variances, and control changes.

Key Points

• The schedule baseline is the authorized snapshot of the schedule model used for performance measurement and control.
• It is established after schedule development and formal approval, and changes require change control.
• It includes planned start and finish dates for activities and milestones, and reflects the critical path at approval time.
• Progress is compared to the baseline to identify variances, trends, and need for corrective or preventive actions.
• Re-baselining is rare and only done when significant, approved changes justify resetting the plan.
• The baseline is stored, version-controlled, and referenced in reports and forecasts.

Purpose

The schedule baseline provides a clear, agreed plan for when work should happen so the team and stakeholders share the same expectations. It enables consistent tracking, variance analysis, forecasting, and transparent decision-making when changes are proposed.

Pre-requisites

• Defined scope baseline (scope statement, WBS, and WBS dictionary).
• Complete activity list with attributes and logical relationships.
• Resource assignments, calendars, and availability confirmed.
• Duration estimates and documented estimating assumptions.
• Risk analysis completed with time buffers or schedule reserves defined.
• Schedule management plan with performance thresholds and measurement methods.
• Stakeholder review of constraints, milestones, and acceptance of planning assumptions.

How to Set Baseline

• Build a resource-feasible schedule model and validate logic, critical path, and float.
• Apply calendars, constraints sparingly, and verify no dangling or open-ended activities.
• Incorporate risk responses with appropriate buffers and schedule reserves.
• Run what-if analyses and adjust the plan to meet objectives and constraints.
• Define the data date, reporting cycle, coding structures, and earned value method if used.
• Document assumptions, exclusions, and the baseline version and date.
• Review with the team and stakeholders; resolve conflicts and resource overloads.
• Obtain formal approval through integrated change control and freeze the baseline.
• Store the baseline in the scheduling tool and configuration system, and communicate it.

How to Use

• Capture actuals and forecasts routinely, and compare to baseline dates and milestones.
• Analyze variances and trends at the activity, path, and milestone levels.
• Apply thresholds to trigger corrective or preventive actions or change requests.
• Use the baseline to communicate impacts, negotiate trade-offs, and support decisions.
• Maintain the baseline unchanged unless an approved re-baseline is authorized.
• Align status updates and reports (e.g., milestone trend charts, SPI) to the baseline.

Change Control Rules

• Any change that alters approved milestone dates or the critical path requires a change request.
• Assess impacts on scope, cost, resources, risks, and benefits before approval.
• Use defined thresholds to determine when to escalate versus handle within management reserves and authority.
• Preserve previous baseline versions and maintain traceability in the change log.
• Only re-baseline when significant, approved changes or resets make the current baseline no longer useful.
• Synchronize updates with related baselines (scope and cost) to keep the plan coherent.

Example

A project is approved with a 10-month schedule baseline and four quarterly milestones. At month 4, a critical activity slips by three weeks. The team analyzes the variance, tests schedule compression and resequencing options, and determines a five-day delay to Milestone 2 remains. The project manager raises a change request with impact analysis; once approved, the updated baseline reflects the new milestone date and is communicated to stakeholders.

PMP Example Question

Midway through execution, a supplier delay pushes the critical path by 12 days. What should the project manager do next with respect to the schedule baseline?

1. Update the schedule baseline to reflect the new dates and notify stakeholders.
2. Analyze impacts and submit a change request per the change control process.
3. Compress the schedule by adding overtime and skip approvals to save time.
4. Escalate to the sponsor to decide whether to continue the project.

Correct Answer: B — Analyze impacts and submit a change request per the change control process.

Explanation: The schedule baseline can only be changed through formal change control. The next step is to assess impacts and seek approval before altering the baseline dates.