Economic historian Karl Polanyi has argued that where barter is widespread, and cash supplies limited, barter is aided by the use of credit, brokerage, and money as a unit of account (i.e. used to price items). All of these strategies are found in ancient economies including Ptolemaic Egypt. They are also the basis for more recent barter exchange systems.[17]

This sort of scenario was so undesirable that societies must have created money to facilitate trade, argues Smith. Aristotle had similar ideas, and they’re by now a fixture in just about every introductory economics textbook. “In simple, early economies, people engaged in barter,” reads one. (“The American Indian with a pony to dispose of had to wait until he met another Indian who wanted a pony and at the same time was able and willing to give for it a blanket or other commodity that he himself desired,” read an earlier one.)
In 2012, the average Canadian had more than $27,000 in consumer debt. Wages are shrinking, costs are rising, and one-third of us are living paycheque to paycheque. “Most of us live beyond our means both financially and ecologically,” says Marta Nowinska, founder and president of one of Canada’s largest bartering communities, Swapsity, which launched in 2010. “Swapping is a viable approach to solving a lot of real problems,” she says. Like Simmons, Nowinska left a Bay Street job to join the world of barter. The idea for Swapsity came to her one day in 2006: she was on the subway and noticed how miserable everybody looked. She started to think about a business that could empower people. At first, she thought people could swap jobs, but dismissed it as unrealistic. Then: what if they could swap other things? She developed a business plan and launched a website.
In late 2012, Toronto even got its own spinoff of Trade School, a model that originated in New York in 2010. The Toronto Trade School holds classes—on anything from spoken word to origami flower–making to bicycle maintenance—and invites students to “pay” with an item or service from the teacher’s barter wish list. It has hosted more than 70 classes.
While one-to-one bartering is practiced between individuals and businesses on an informal basis, organized barter exchanges have developed to conduct third party bartering which helps overcome some of the limitations of barter. A barter exchange operates as a broker and bank in which each participating member has an account that is debited when purchases are made, and credited when sales are made.

Since the 1830s, direct barter in western market economies has been aided by exchanges which frequently utilize alternative currencies based on the labor theory of value, and designed to prevent profit taking by intermediators. Examples include the Owenite socialists, the Cincinnati Time store, and more recently Ithaca HOURS (Time banking) and the LETS system.