Educational interaction and communication are classic topics of educational research. The first serious initiations are associated with the 1960s and researchers who focused on the microanalysis of school communication (e.g. the methods of Bellack, Flanders and Taber; in the Czech context, works by Mareš, Gavora, Tollingerová, Průcha and others). At the time of their origin, these usually represented very laborious quantitative perspectives on educational interaction and communication, all of them based on models of mass education. Although both the “school itself” and the research methodolog y have changed since then, these studies are still viewed as inspirational for the research projects of today. The author describes a modified method of FIAS which is applicable for research in teacher-to-pupil communication under conditions current in Czech primary and lower secondary schools. It follows the familiar categorical system of N. A. Flanders but uses different categories of activities and applies computer software.