This chapter discusses the formal and less formal ways in which Christians in the first millennium, especially during the early Middle Ages, could compensate for transgressing moral rules. Monastic ways of confessing and atoning for transgressions were introduced to specific lay audiences. Especially in the insular world, penitential books were composed that provided guidelines for this process. Such works were closely connected to other forms of ecclesiastical regulation. In the Carolingian world, penance became an issue of central concern, discussed at councils and in canonical collections. As a consequence, a substantial number of new texts were composed and disseminated widely. Such works of Carolingian inspiration reached an audience outside of the Carolingian realms: in Spain, Italy, and England. They were also increasingly included in canonical collections. The close connection between penitential books and canonical collections suggests that both genres could be employed in diverse settings. Distinctions between public and private penance, or between penance and jurisdiction (judicial punishment) are not as clear or self-evident as used to be thought.