You need a physical object and you have the money, you buy it. You need a service, you pay for it. Our economy tends to be straightforward.
But there are other ways of doing things, and the Ashland-based Post Growth Institute lays out the vision for one possible exchange, an "offers and needs market." People bring material goods or skills to the market to offer in exchange for something else.
Crystal Arnold is the Director of Education for PGI. She visits with an outline of how the market works, prior to an upcoming webinar to offer it to the public.