Consumer awareness, enhanced by legally imposed green law constraints, have lead to the need for safe return of products from the field as well as more environmentally friendly products. As a result, logistics planning must now consider both forward and return flows of products, parts, subassemblies, scrap and containers. It seems that an entirely new spectrum of goods has emerged at what was once considered the end of the supply chain. These goods include:

• Products that have failed, but can be repaired or reused.
• Products that are obsolete but still have value.
• Unsold products from retailers.
• Recalled products.
• Parts repaired in the field that still have value.
• Items that have secondary usage, i.e. items that have another usage after they have exhausted their original use.
• Waste that must be accounted for and disposed of or used for energy production.
• Containers that...