Kindergarten readiness has received significant attention in recent years in response to concerns regarding preparing young children for school and beyond and mitigating persistent achievement gaps. Currently, there is little consensus around what factors drive and define kindergarten readiness. In this study, we sought to expand understanding of perspectives on how kindergarten readiness is defined, the role of early learning standards for defining kindergarten readiness, views about the implications of defining kindergarten readiness, and the utility of state definitions for guiding kindergarten readiness practices. Data sources included surveys, focus groups and interviews with individuals representing state early childhood education agencies, and existing state kindergarten readiness definitions. Collective study findings indicated that there is evidence of persisting variation in perspectives on how to define kindergarten readiness, reflecting continuing tension about the construct's meaning. Although state policy makers tend to view kindergarten readiness through a developmental lens rather than as a ready‐or‐not statement, they also emphasize the role of child attributes such as age or skills and knowledge outlined in early learning standards. Additionally, participants reported both positive views and apprehension around adopting a common definition to guide efforts to promote readiness. This investigation underscores the need for further consideration of adopting a universal, multifaceted kindergarten readiness definition that calls attention to the role of child and environmental inputs as a starting point for preparing all young children for school.