ETRM systems are, by their nature, complex software products as the software must mirror the full complexity of the commodities industries, markets, and assets that they serve. Spanning from contract administration through invoicing and settlement, the business processes involved in commodity trading varies greatly. This variation is created by the unique combinations and nature of the physical or financial commodity or commodities traded, as well as by the industry segment (power generation/trading, gas production/trading, agricultural production/trading, etc.), the assets employed in the supply chain(s) and geographic differences (North American power vs. European vs. Japan, for example).