Schedule Management Cheat Sheet

Schedule Management — Quick Reference

Activity Dependencies

Type	Description	Common?
Finish-to-Start (FS)	B starts after A finishes	Most common
Start-to-Start (SS)	B starts when A starts	Allows parallel work
Finish-to-Finish (FF)	B finishes when A finishes	Less common
Start-to-Finish (SF)	B finishes when A starts	Rare

Dependency Types

• Mandatory (hard logic) — Legally or physically required
• Discretionary (soft logic) — Best practice, preferred sequence
• External — Depends on factors outside the project
• Internal — Within the project team's control

Critical Path Method

1. Identify all activities and dependencies
2. Forward pass: Calculate Early Start (ES) and Early Finish (EF)
3. Backward pass: Calculate Late Start (LS) and Late Finish (LF)
4. Float = LS − ES = LF − EF
5. Critical path = path with zero (or least) float

Schedule Compression

Technique	How	Risk	Cost
Crashing	Add resources to critical path	Same or slightly more	Increases
Fast Tracking	Overlap activities	Increases significantly	Same

PERT Estimates

• Expected duration = (O + 4M + P) / 6
• Standard deviation = (P − O) / 6
• 68.26% confidence: Mean ± 1σ
• 95.46% confidence: Mean ± 2σ
• 99.73% confidence: Mean ± 3σ