The great expansion of engineering manpower has contributed to the productivity increase and economic growth in the United States. The goal of this dissertation is to shed new light on the employment of engineers by using previously unavailable firm data in traditional economic models as well as in models developed in the dissertation. In order to perform these analyses data were obtained from very large firms in the aerospace, electronic equipment, chemical petroleum industries for 1957-1976. The dissertation consists of two central parts. The first part examines the factors which explain the level of a firm's engineering employment and the ability of the firm to predict and achieve future employment levels. The level of a firm's engineering employment is explained to some extent by a relationship among a firm's sales, R&D expenditures and wage rate for entry level engineers. In addition, it is suggested how this relationship could be used for the forecasting of future employment levels. The ability of a firm to predict its future employment levels is shown to be negatively related to the length of the forecasting interval, the industry's technical complexity (as measured by the ratio of R&D to sales) and the industry's dependency on the government for financing its R&D expenditures or for purchasing its final product. For firms in the chemical and petroleum industry during 1957-1968 the ability of a firm to achieve future employment levels is found to be negatively related to its desired percentage increase in engineering employment and positively related to the change in its net income. The extent to which this adjustment took place within one year was very similar in both industries and similar to that found for R&D expenditures. The second part examines the variation in the degree-level distribution and salary structure among firms within an industry which is shown to be explained in part by firm size, the ratio of engineers to total firm employment and the ratio of scientists to engineers. In addition the degree-level distribution is found to be sensitive to changes in salary differentials among degree levels. Further, the changes in the demand and supply conditions in the engineering labor market which brought about changes in relative salaries and employment among degree levels are discussed. Finally, the engineering population has aged over time and the impact of this aging on the rate of technological innovation is analyzed. The older the engineer, the greater the proportion of his knowledge which is likely to be obsolete; beyond a certain age an engineer's creative output may decline.
