report provides the results of focus group studies and human factors laboratory studies to investigate issues related to America’s Missing: Broadcast Emergency Response (AMBER) alerts, disaster response and evacuation (flooding, hurricane evacuation, and terrorist attacks), planned special events, and adverse weather and environmental conditions in order to design effective messages for display on dynamic message signs (DMSs). Focus group studies were conducted in six cities in Texas to obtain driver views of the above issues and to discuss driver information needs. The results of the focus group studies were used as the basis for more extensive human factors laboratory studies that were then conducted in six cities in Texas. The laboratory...