Energy prices have moved up considerably since the end of 2002, reflecting supply and demand factors. In the short run, prices are likely to remain high in an environment of strong world economic growth and a limited ability to increase energy supplies. Moreover, prices are likely to be volatile in the near term, given the small margins of excess capacity to produce crude oil or natural gas that traditionally have buffered short-run shifts in supply and demand. However, in the long run, market forces will respond. The higher relative prices of energy will create incentives for businesses to create new, energy-saving technologies and for energy consumers to adopt them.