The study of temperament profiles is considered a person-centered approach to understanding temperament, as it takes into consideration the complex combinations and interactions of multiple traits that characterize an individual. However, most studies of temperament profiles have focused on reactive traits in infants and toddlers using parent ratings and/or laboratory conditions and since outdated methodologies. This study contributed to the temperament profile literature by exploring profiles based on parent and teacher ratings of reactive and regulatory traits of young children in kindergarten using the modern statistical technique of latent profile analysis. Kindergarten is a unique and critical time in development in which children are suddenly learning new academic, social, and self-regulatory skills as they begin formal education. Parent and teacher ratings of kindergarteners’ temperament were analyzed separately and the behavioral profiles produced by each were described. When only reactivity traits were included in the analyses, the profiles that emerged were mostly consistent with the three to four profiles that have been found in previous studies, including inhibited, exuberant, average, and/or low reactive profiles. When both reactive and regulation traits were included in the analyses, more nuanced profiles emerged that generally reflected subdivisions of the traditional reactivity profiles found in the literature but with varying levels of regulation. There were many similarities but important distinctions among the profile numbers, temperament patterns, and proportion sizes of the parent and teacher profile solutions. Neither child age nor child sex were found to be important predictors of profile membership. Despite its own limitations, the present study serves as a model for how previous methodological limitations in the field may be addressed to enhance our understanding of the complexity and nuances of temperament development and continue to push the field forward. Through such person-centered approaches, the field may one day guide parents, educators, and practitioners towards meeting the diverse needs of children with various temperament dispositions.