Kivas are an important Southwestern architectural form. 'Kiva' is a Hopi word used to refer to specialized round and rectangular rooms in modern Pueblos. Modern kivas are used by men's ceremonial associations. Archeologists assume that ancient kivas served similar functions. Chacoan kivas are round, usually semi-subterranean, and built into great houses. Like modern kivas, they were entered by a ladder from the roof down to the center of the kiva floor. During ceremonies today, the ritual emergence of participants from the kiva into the plaza above represents the original emergence by Puebloan groups from the underworld into the current world. Late in the Chaco sequence two-to-three story tower kivas were also built.

Archeologists believe kivas developed out of earlier pit structures that were used as dwellings. Chacoan kivas have formal features like fire pits, floor vaults, wind deflectors, and benches, and contain evidence of domestic as well as ritual life. Historically, Puebloan men used kivas as sleeping quarters and meeting rooms at various times of the year.

Kivas come in all sizes. The largest are called great kivas. Two great kivas in Chaco Canyon - Casa Rinconada and Kin Nahasbas - are free-standing; the other great kivas are located in plazas of great houses. Great kivas are assumed to have housed community-level activities, whether ceremonial, social, or political. Small kivas are sometimes called clan kivas, and suggest use by small kin-based family groups.