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).
Barter is a system of exchange by which goods or services are directly exchanged for other goods or services without using a medium of exchange, such as money. It is distinguishable from gift economies in that the reciprocal exchange is immediate and not delayed in time. It is usually bilateral, but may be multilateral (i.e., mediated through barter organizations) and usually exists parallel to monetary systems in most developed countries, though to a very limited extent. Barter usually replaces money as the method of exchange in times of monetary crisis, such as when the currency may be either unstable (e.g., hyperinflation or deflationary spiral) or simply unavailable for conducting commerce.
She was about to quit the project when she received a cascade of good news: six new women signed up as Barter Babes, more than she’d ever had before at one time. Then City Television contacted her for an interview segment—one of her Barter Babes had mentioned her trade to a friend at the station. After that, social media mentions of Barter Babes blew up.
Her answer came, finally, in an unlikely place: at a bar on Robson Street in Vancouver during the Winter Olympics. It was close to midnight, and she was waiting in line for a drink. All around her, people were partying—except for the two women in front of her, who were dissecting the differences between tax-free savings accounts and RRSPs. Simmons barged in to their conversation. “What do you want to know about TFSAs?” she asked. “What’s your goal?” She pulled the two aside and, for 20 minutes, gave an impromptu finance session. As a gesture of thanks, the two women bought Simmons and her group a round of beer. “I can’t afford financial advice,” one of them told Simmons, “but at least I can give everybody here a beer.” Then, Simmons felt like a cartoon megawatt bulb appeared over her head. It is all you can do, she thought. It is all you can do. There, in the middle of the crowded bar, she blurted, “Oh my god! I’m bringing barter back!”
Other anthropologists have questioned whether barter is typically between "total" strangers, a form of barter known as "silent trade". Silent trade, also called silent barter, dumb barter ("dumb" here used in its old meaning of "mute"), or depot trade, is a method by which traders who cannot speak each other's language can trade without talking. However, Benjamin Orlove has shown that while barter occurs through "silent trade" (between strangers), it also occurs in commercial markets as well. "Because barter is a difficult way of conducting trade, it will occur only where there are strong institutional constraints on the use of money or where the barter symbolically denotes a special social relationship and is used in well-defined conditions. To sum up, multipurpose money in markets is like lubrication for machines - necessary for the most efficient function, but not necessary for the existence of the market itself."