Research Findings: The aim of this study was to investigate emotional state talk between teachers and their students in 81 early childhood classrooms during shared book reading. Teachers shared with their students an experimental emotion narrative book. Preliminary analysis of teachers' and children's transcribed utterances during reading addressed the frequencies of emotional terms, form (question vs. comment), and content (emotion identification, emotion causality, emotion inference, or non-emotional content). Sequential analysis evaluated contingent relations between the book text and teachers' comments and questions about emotions as well as between teachers' and children's contingent responses to each other. Results showed emotional excerpts from the book were significantly associated with teachers' questions and comments about emotion identification. Children were highly specific and responsive to teachers' emotional state talk, and children's comments about emotions evoked further considerations from teachers about the same topics. Practice or Policy: Our results highlight the importance of the presence of emotional terms in the book text to stimulate emotional state talk. Given the value of emotional state talk for children's emotional development, teachers must be informed of preschoolers' ability to consistently participate in classroom discussions about emotions, even when complex topics like causality and inferences are addressed.