Complementary currency systems are based on principles of solidarity and contestation of the regular currency systems, so their prices may differ from those in the regular economy. This study aims to explore that assumption and discusses in what ways and for what reasons some prices are different. Based on data collected in Buenos Aires during 2004, it researched the ways in which various prices in the Argentine Redes de Trueque followed those in the regular economy or internal considerations of the system, as relative supply and demand, production costs, and ethical and institutional factors. It found substantial evidence against the assumption that prices in the CCS were a direct conversion of prices in pesos. Each node was organised as a price network in which critical prices - namely those of groceries bought in pesos - were used as reference for other prices. The result was a power asymmetry in favour of those who had pesos to get supplies in supermarkets, but some traders refrained from obtaining the maximum profit and preferred to ask a “fair price”. Notions of fairness and shared values, however, varied widely, like the effectiveness of the institutional controls put in place to keep prices down.