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Value Stream Map

How does value flow — and where does time die?

VALUE STREAM MAP
════════════════════════════════════════════════════════════

  [TRIGGER]
      │
      ▼
  ┌─────────┐
  │ STEP 1   │   C/T: ___   Wait: ___   %C&A: ___%
  └────┬─────┘
       │ ░░░░░░░░░ (wait time)
       ▼
  ┌─────────┐
  │ STEP 2   │   C/T: ___   Wait: ___   %C&A: ___%
  └────┬─────┘
       │ ░░░░░░░░░░░░░░░░░░░░░ (bottleneck!)
       ▼
  ┌─────────┐
  │ STEP 3   │   C/T: ___   Wait: ___   %C&A: ___%
  └────┬─────┘
       │
       ▼
  [OUTPUT]

  Flow Efficiency = Cycle Time / Lead Time x 100
  World-class: >40%   Good: 20-40%   Typical: 5-15%

════════════════════════════════════════════════════════════

The Value Stream Map is the second flow engineering map. It reveals where waste hides — wait time is usually 10-100x cycle time.

Metrics​

MetricMeasuresWhy It Matters
Cycle Time (C/T)Time to complete one unitThe work itself
Wait TimeTime between stepsWhere flow breaks
%C&A% Complete & Accurate at handoffQuality of flow
Lead TimeC/T + WaitTotal time from trigger to output
Flow EfficiencyC/T / Lead TimeRatio of value-added to total time

Seven Wastes​

Toyota's waste categories adapted for knowledge work:

WasteManufacturingKnowledge Work
WaitingParts not arrivedWaiting for approval
OverproductionMaking too muchBuilding unused features
ReworkDefectsBug fixes, revisions
MotionWalking to toolsContext switching
TransportMoving materialsHandoffs between teams
InventoryExcess stockWork in progress
Over-processingUnnecessary polishGold-plating features

Gate​

Before moving to Dependency Map:

  • All steps documented with cycle time
  • Wait time measured between steps
  • Flow efficiency calculated
  • Bottlenecks identified and ranked
  • Waste types categorized
  • Improvement opportunities prioritized

If flow efficiency is below 15%, address bottlenecks before adding features.

Context​