professional bureaucracies that hire professionals as salaried employees.
Professional bureaucracies create employment opportunities for professionals in two ways. First, because hospitals and other professional bureaucracies have access to more resources than do solo practitioners, they can afford equipment and facilities that enable them to provide services that clients could not otherwise obtain. The availability of such services, in turn, increases the population's demand for professionals' expertise, thereby enabling professional bureaucracies to support more practitioners per capita than would have worked under a regime of solo practice. Second, professional bureaucracies create an organizational context supportive of specialization. Because professional bureaucracies collocate practitioners, they can employ specialists and still provide broad expertise to clients. However, providing breadth of expertise under a regime of specialization means that more practitioners must become involved in a case. Thus, as specialists replace generalists, more professionals are required to meet a client's needs.
The increasing economic importance of scientific knowledge is the second reason for the expansion of the professional and technical workforce. One researcher has estimated that, by the 1960s, scientific output was doubling every 6 to 10 years, a rate of growth "much faster than that of all nonscientific and nontechnical features of our civilization" (Price, 1986:141). He also noted that 90 percent of all scientists who ever lived are alive today. The explosive growth of science has been sustained, in part, by the realization that scientific and technical knowledge can generate considerable profit. The commercialization of chemistry and physics during the late 19th and early 20th centuries gave rise to the industries on which the U.S. economy currently pivots: aerospace, automobiles, energy, pharmaceuticals, petrochemicals, and electronics. Advances in the life sciences, especially in immunology, microbiology, biophysics, and biochemistry, underwrote the expansion of the health care industry that began after World War II. More recently, molecular biology and its associated technolo-