A significant task of planners involved in emergency disaster management is planning for the optimal assignment of people to emergency shelters. This complex task depends on the available infrastructure and roadway characteristics and can take on additional complexity when older populations are considered because their health conditions may deteriorate during a disaster. Older people may also require special assistance even though they are not listed in the registries of people with special needs. This paper specifically focuses on the assignment of older populations to shelters. The paper presents a spatial optimization methodology based on data from a geographic information system. The focus is on the segment of the population 85 years old and older and on the use of potential benefits of cross-county collaboration in special needs shelter (SpNS) management. Such collaboration can help in using additional shelter capacity between neighboring counties (a) to overcome the lack of capacity in a county and (b) to assign the demand to a close shelter across county borders. The methodology was applied to a case study of five counties in the Florida Panhandle. Because the SpNS demand for the 85+ age group was not known exactly, a sensitivity analysis was conducted for different demand levels. From an emergency management perspective, this type of cross-county utilization can provide a means to use existing regular shelters in multiple counties to serve the 85+ population.