Several years ago, Mark Miles’ Greener Pastures lawn care service was facing bankruptcy. He needed to create new income streams, but he had little cash to invest in traditional marketing. So he joined a barter exchange, and with a $10,000 credit line in “trade dollars,” he was able to barter his services for various business needs, including marketing-and through this, he grew his customer base without cash. “Barter was my vehicle to do the marketing to get new cash customers,” he said. The move has turned his business around, and now, Greener Pastures is estimated to be worth $20 million. Bartering-the cashless trading of goods and services-is the most ancient form of commerce. Yet, many contemporary businesses are taking a second look at bartering as...