One of the chief problems confronting Southwestern archeologists today is the definition of relationships between the Anasazl and the Mogollon, for regardless of the position taken as to their taxonomic status, the fact that differences did exist in some degree demands investigation. Such investigation is by no means easy, because there are many similarities between the two groups. To understand these, it is necessary to control the relative chronology; and for this our evidence is poorest for the period most critical in the relationships, that is, prior to A. D. 600. Nevertheless, recent advances in our knowledge make such an attempt necessary.