The twenty-two articles collected in this book have had and continue to have a considerable impact on the development of econometrics. Since limits must be set in such a broad field, selections have been restricted to articles dealing primarily with statistical methods or applications of statistical methods to economic models. In the study of economics, preference functions vary enormously among individuals; therefore the editors have exercised two choices—balancing articles in econometric methodology with those in econometric application. The result is both discerning and representative, with chapters ranging over such subject matter as the stock market, hybrid corn, international comparison of household expenditure patterns, the demand for durable goods, and the durability of durable goods, as well as the use of econometric models in guiding economic policy and identification problems in model construction. There are also a number of chapters on simultaneous equations: three-state least squares, canonocal correlation theory, alternative estimators, cost of approximate specification, and the statistical implications of a system of simultaneous equations. Both students and professional practitioners of econometrics will find this a convenient reference book and a historical document of the growth and changing emphasis of the subject over the past three decades. Contributors: Alfred Cowles, 3rd, R. Frisch and F. V. Waugh, T. Haavelmo, C. F. Roos and V. S. Von Szeliski, H. B. Mann and A. Wald, L. R. Klein, T. C. Koopmans, H. B. Chenery, T. M. Brown, R. L. Basmann, Z. Griliches, H. S. Houthakker, J. Tobin, J. W. Hooper, I. Adelman and F. L. Adelman, R. Stone and D. A. Rowe, T.-C. Liu, F. M. Fisher, A. Zellner and H. Theil, T. J. Rothenberg and C. T. Leenders, M. Nerlove, and G. C. Chow.