As Orlove noted, barter may occur in commercial economies, usually during periods of monetary crisis. During such a crisis, currency may be in short supply, or highly devalued through hyperinflation. In such cases, money ceases to be the universal medium of exchange or standard of value. Money may be in such short supply that it becomes an item of barter itself rather than the means of exchange. Barter may also occur when people cannot afford to keep money (as when hyperinflation quickly devalues it).
Consumer-based barter systems aren’t the only trade in town, either. In the GTA, there is a robust business-to-business barter system, similar to wir but on a smaller scale. Businesses sign up for a service—there are several available—and trade unbilled work hours or dust-covered inventory for goods and services they couldn’t otherwise afford, especially during recessionary times: often things that attract top talent and retain big clients, such as advertising, promotional gear or client perks.