This article presents the main results of a qualitative study intended to describe and interpret preschool teachers' Subjective Theories (STs) about family discipline. Episodic interviews were conducted with 8 preschool teachers from 4 low-SES (socioeconomic status) and 4 high-SES educational centers in the Coquimbo region, who were divided into 2 age groups. The data were analyzed using some grounded theory procedures. The results obtained, based on the STs held by the participating teachers, revealed what they believe about the way in which parents and/or caregivers exert discipline nowadays, along with the main factors that influence this issue. The discussion analyzes the impact of these subjective theories as regulators of their educational practices, considering their explanatory power and orientation towards action.