The Ws of Safety: Treating the System, Not the Symptom

 

This October 2025 TRR journal article introduces a “Ws of Transportation Safety” framework to strengthen the Safe System Approach in pursuit of Vision Zero.
October 17, 2025
Paper about the Ws of Safety

The Ws of Safety: Treating the System, Not the Symptom

 

This October 2025 TRR journal article introduces a “Ws of Transportation Safety” framework to strengthen the Safe System Approach in pursuit of Vision Zero.
October 17, 2025

The US is entering its second decade of Vision Zero, a road safety initiative designed to eliminate all traffic-related deaths and serious injuries. But the conversation has evolved.

For years, transportation professionals relied on the traditional Es of safety—engineering, education, enforcement, and emergency services. These reactive measures, while important, often operate in silos and miss the bigger picture of how transportation systems as a whole can reduce risk.

A new article in the Transportation Research Record (TRR), authored by several of our safety experts, shifts the focus from Es to the Ws—asking who, what, when, where, and why. The Ws of Safety framework can help uncover systemic risks and guide upstream interventions on the road to Vision Zero.

For transportation planners, engineers, and public agencies, the takeaway is clear: Vision Zero 2.0 requires more than refining the old tools. It calls for embedding the Safe System Approach into everyday practice and addressing systemic issues to shape roadway safety long before a crash occurs.

The Ws of Safety can help us achieve these goals.

Read Getting a “W” for Safety: Flipping the Script on the Safety “E”s in Search of a Winning Strategy:

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Contributors

headshot of Meghan Mitman

Meghan Mitman

Regional Principal-in-Charge

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Staff photo of Terence Zhao

Terence Zhao

Senior Transportation Planner

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Staff photo of Adrian Engel

Adrian Engel

Principal

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