Experimental research on college teaching began with single variable studies of class size and lecture vs. discussion. During the 1930s, research on student ratings of teachers began, and following World War II, studies of college teaching and learning became more common. In the decades from then to the 1980s, research moved to concern with a broader range of variables, to analyses of interactions between student and classroom variables, and to attention to processes as well as products resulting from teaching. Research on college teaching clearly meets Conant's criteria for a scientific field: progress in theory, methods, and established knowledge. Moreover, we now have demonstrated that educational research can contribute to educational practice. Has research on college teaching made progress? Conant (1947) argued that a field could be called scientific when knowledge has accumulated, progress is evident in the development of new conceptual schemes resulting from experiments and observations, and the conceptual schemes lead, in turn, to more research. He suggested that one of the tests of whether a field qualifies would be to imagine the reaction of the pioneers in the field if they were to be brought back to life and viewed the current status of the research and theory. Would they acknowledge that there had been progress?