Book excerpt: Studies of prehistoric exchange of goods provide information about the types of economic interaction, social organization, or political structures in which prehistoric peoples were engaged. Long-distance exchange is a special situation where the materials exchanged crossed significant boundaries, whether they were geographic, social, political, or otherwise. By examining the types and quantities of goods exchanged, along with the directions and distances they moved, archaeologists are able to examine the dynamic properties of exchange systems, i.e., how they operate and why they undergo change. The purpose of this volume is to present a number of case studies of long-distance exchange from around the world which demonstrate the use of geochemical analysis of artifacts to find evidence of exchange. More important than the use of analytical technique employed or the types of artifacts studied are the interpretations themselves which illustrate that exchange studies are maturing and helping archaeologists to develop more accurate models of exchange.