In the course of the following discussion the reader will no doubt grow weary of the word ‘pottery’. However, before he decides that the ancient Southwesterners did nothing but sit around and make pottery or that the writer is the victim of a pottery mania, it might be profitable for him to cast an observant eye about the room in which he is sitting. After the passage of five hundred or a thousand years how much would survive, if one discounted material not available in the most ancient times such as metal, glass, and plastics? High at the top of the list will be dishes, ashtrays, and vases of china or porcelain—the modern counterparts of prehistoric pottery. Also, it may readily be seen that there are differences in style between older and more recent objects. A vase purchased this year is likely to differ in many respects from one acquired even as little as twenty-five or fifty years ago. An amazing amount of information can also be derived from the microscopic study of pottery. Trained investigators can examine thin sections under a microscope and identify the materials used in manufacture and often locate their sources. With this information it is then possible to determine whether pottery was locally made or imported. This tells us a great deal about the cultural relationships of ancient people, for trade implies contact between people which will affect other phases of their culture. In prehistoric times, when people lacked rapid means of transportation and communication, human groups were naturally isolated as they can never be again, but even then cultural units were affected by the activities of the inhabitants of other regions. Accordingly, we cannot see the ancient life of the Southwest in true perspective if we do not know something of the inter-relations of the various cultures. One of the great boons to southwestern archaeology has been dendrochronology—a system which has made it possible to establish an absolute count of years through the pattern combinations of annual growth rings of trees. The inevitable question which arises in connection with anything prehistoric is “How old is it?”, and prior to the introduction of tree-ring dating it was difficult to answer except in relative terms, for in the Southwest we are dealing with a people who left no written records. It is remarkable, however, how much had been accomplished in establishing relative chronology through the use of stratigraphic studies and the cross-checking of sites.