The first of its kind, a seminar on Production Theory was held at the University of Karlsruhe during May and June 1973. Seven of the nineteen resource participants were from Canada, France, the Netherlands, Sweden and the U.S.A., to make the seminar an international symposium. The other par- ticipants involved a variety of experts from German univer- sities. Karlsruhe supplied the predominant part of the Ger- man contributors. For the discussions of the seminar twenty papers span- ning a large part of production theory were prepared and these papers are herewith published as a coherent collection under the title: KARLSRUHE SEMINAR ON PRODUCTION THEORY. Papers on scalar valued production functions are orga- nized in Part 1. Several of these provide new characteri- zations of CES productiop functions, partly in connection with technical progress, and two others are related to homothetic production functions. Six papers on multisectoral production models have been included in Parts 2 and 3, addressed in part to problems of dynamic structures, disaggregation and relaxation of simple homogeneity. Turning next to more general production models, Part 4 contains five papers involving set valued production func- tionsor production correspondences, dealing with such topics as efficient pOints, stochastic aspects, homogeneity, homo- theticity and the law of diminishing returns.