Pueblo I to III Mesa Verde settlements typically have one protokiva or kiva for each block of six to nine rooms, a pattern indicative of kiva use by a relatively small and common social segment such as an extended family or minimal lineage. These ordinary small Pueblo I protokivas and Pueblo II and III kivas were probably used for both ritual and domestic activities. Chacoan outliers in the Mesa Verde area have fewer and larger kivas, and a less regular patterning of kivas to room blocks. Kivas at Chacoan sites may have functioned at a larger scale of social integration than at Mesa Verde settlements. At roughly A.D. 1300, approximately coincident with the abandonment of the Mesa Verde area, most Puebloans shifted from a Mesa Verde-like pattern of many small kivas to one of large plaza-oriented sites with only a few relatively large kivas. Following Steward (1937) and Adams (this volume), this suggests a larger integrative scale for kiva use, and stronger village-level organization. Continuities in kiva architecture and ritual features suggest that aspects of the religious ideology associated with earlier kivas were incorporated into the new organization.