A further prevailing trend over the last decade or so has been a dramatic reduction in the number of suppliers from whom an organization typically will procure materials, components, services, etc. In some cases this has even extended to "single sourcing : whereby one supplier is responsible for the sole supply of an item. _Severa well- documented cases exist where major supply chain disruptions have been caused because of a failure at a single source. Even though there are many benefits to supplier base reduction it has to be recognized that it brings with it increased risk.