Flander's interaction analysis is a technique for analyzing classroom interactions between teachers and students. It involves encoding verbal exchanges into categories to quantify dimensions like communication, coordination, and integration. Flander developed 10 categories to classify teacher talk, student talk, and silence. The process involves an observer encoding exchanges in real-time, then decoding the data through matrices to analyze proportions of interaction types and identify constructive vs vicious interaction cycles. Advantages include providing teachers feedback to improve instructional quality and measuring social-emotional climate.