Lonecroft Inc. sells a range of products across the US using a network of 10 regional distribution centers (DCs) to supply local retailers and wholesalers. In the past, most of their products were made in Asia, but they recently shifted production to Ciudad Juarez, Mexico and they currently lease one central distribution center in El Paso, TX. Currently all products are sent from Ciudad Juarez across the border to the El Paso DC, from where they are sent to the 10 regional DCs. These 10 DCs have average weekly demands as shown in Table 1 and they are resupplied each week by truck using a variety of carriers. Lonecroft expects their business to grow as long as they can be effective in maintaining low costs and improving their service with fast delivery times. In light of the recent increases in competition and the growing importance of service (reducing delivery times) Lonecroft is seeking a redesign of their distribution system to the ten regional DCs. Lonecroft in considering replacing the one central DC in El Paso with one or more "origin DCs" located strategically around the US to improve the level of service offered. They have identified five possible locations for