The approaches necessary for estimating earthquake effects on railroads are different for developing design criteria or post‐earthquake response policies and for developing railroad damage scenarios. In developing design criteria or post‐earthquake response policies, the probability of ground motions exceeding a particular level is a primary concern. Developing damage scenarios, on the other hand, involves describing hypothetical effects for assumed ground motions. The identification of potential problems is the greatest benefit of disaster scenario development to railroads. Developing the Great Southern California ShakeOut Scenario revealed areas in which advance planning and arrangements by the affected railroads could reduce delays in repair work or improve the efficiency of operation during recovery. These include arranging emergency waivers for permits and similar governmental requirements, developing arrangements to accommodate earthquake‐related conflicts between commuter and freight operations, advance arrangements for emergency use of helicopters, and physically securing equipment at the San Bernardino dispatching center to reduce damage.