On 25-26 January 2003, a simulated mass-casualty exercise called ShadowBowl was conducted. A mass-casualty incident is an event in which local response capabilities are overwhelmed, and outside resources must be integrated as rapidly as possible to mitigate the situation. This article provides an account of the event, observations, and suggestions for improvements from the CRASAR perspective. ShadowBowl consisted of two tests, the first of which was a simulated earthquake response on 25 January 2003 and the remainder of which was an exercise conducted in parallel with Super Bowl XXXVII, with personnel and equipment on site at Qualcomm Stadium in San Diego, California, and across the country, in case a terrorist attack occurred. Capabilities that were demonstrated and tested include environmental monitoring (using sensors to detect radiation, water quality, and fire) and chemical hazard mitigation. This exercise was significant because it exposed a number of issues in a realistic emergency scenario, and the findings from the exercise can help to improve readiness for the next real disaster. Important lessons learned from ShadowBowl include what failed unexpectedly, the difficulty involved in performing what would otherwise be considered mundane tasks, and the ideal configuration of a local command center for specialists trying to use data coming from robots in the field. These lessons encompass critical components of reachback: communications, human factors, and adherence to standards. This article discusses the impact of unexpected failures on communications and other equipment, errant expectations, and information standards (synchronization and data formats).