This chapter critically reviews and complicates three premises of the standard historiography of early-medieval monasticism: monastic life turned at an early stage into a “regular life,” lived according to a written rule; the practice of following a normative written rule was stable, not subject to much historical change; there was an organic evolution that culminated in the implementing of the Rule of Benedict as the unifying norm for monastic life in the context of Carolingian monastic reforms. The chapter complicates these notions on the basis of four case studies: the “angelic Rule” of Pachomius and its role in creating a monastic origin myth; the sancta regula of Caesarius as a way to achieve collective sanctity; the Regula Columbani as a program to unify a monastic movement; and the Regula Benedicti in its two manifestations: as a document revealing a late-antique attempt to organize an ascetic community; and as a Carolingian instrument of reform. Monastic rules are not only different in their content and in their disciplinary program, but each of them carries a different understanding of normativity and a distinctive idea of what the term “rule” (regula) really means.