This paper is concerned with the structural and cultural characteristics of research organizations that influence the making of major discoveries in twentieth-century biomedical sciences, especially characteristics of research organizations that repeatedly make major discoveries across time. Although most of the empirical analysis for these findings is based on research organizations in the United States, we also make some reference to research organizations in other nations. This paper is part of a larger study involving structural and cultural characteristics of biomedical research organizations in four countries. Why do research organizations vary in their capacities to make major discoveries in biomedical science? Science, especially in the twentieth century, has been very dynamic and has grown in unpredictable ways. Because most research organizations experience considerable inertia and change rather slowly, they have considerable difficulty in adapting to the fast pace of scientific and technological change. Too often, a research organization has been a world-class leader in an area of science, but because of organizational inertia and failure to adapt to new trends, it has lost its leading edge.

This paper argues that organizations require distinctive structural and cultural characteristics if their scientists are to make major discoveries time and time again. It is to the identification of these characteristics that this research is addressed. The questions posed in this research have their bases in the sociological literature that is concerned with how the structural and cultural characteristics of organizations influence the making of radical innovations. There is a vast and excellent