This article links the contribution of process-product studies in developing the theoretical framework of educational effectiveness by pointing out the importance of teacher behavior in the classroom. The role that Jere Brophy played in this evolving research is described within the various phases of teacher effectiveness research. Process-product studies revealed the importance of moving from investigating the personal characteristics of teachers to identifying characteristics of effective teaching practices. Research on factors other than the teacher behavior, conducted during the last three decades, have not generated empirical support to show that these factors have direct effect on student achievement and only few of them reveal indirect effects through influencing teacher behavior in the classroom. It is also argued that current models of educational effectiveness research drawn from Brophy's research further the development of constructs generated through process and product studies. We additionally refer to the dynamic model of educational effectiveness and show how the original ideas in the process-product studies were taken into account in describing and analysing the dynamic nature of effectiveness and expand them further by introducing a multidimensional approach to measure the impact of these factors and grouping of factors on student learning outcomes.