In this article I have traced new developments in the integrated system of production and distribution of three manufacturing companies: automobile, steel, and semiconductor manufacturers. These three companies I have taken up in this paper refined their systems in the mid 1990s. I have tried to explore the similarities and differences in their respective developments. Section one presents a brief explanation of the integrated system of production and distribution as one of the competitive edges of big manufacturers. The production system of major Japanese manufacturers nowadays cannot be classified anymore as a classical type of mass-production of a single standardized product. It should be classified as a flexible production system of diversified products. Major companies are offering not only multiplied product lines but also a great number of product variations per line. With the proliferation of the product variations, it has become more difficult and complex for manufacturers to make adjustment between their production and market demand for their products. In order to solve the problem of matching supply to demand they need closer and tighter coordination between production and sales of their products. The integrated system of production and distribution of manufacturing companies has been established for the purpose of making this coordination successful. In sections 2-4 I have referred to some findings from the field research I conducted on these three major manufacturing industries recently. I have introduced the following conclusions in the section five : (1) Smaller lot size of production plannig and shorter length of leadtime for production scheduling prior to actual production were critical factors in the success of the coordination of manufacturing with sales. The smaller the lot size of planning and the shorter the leadtime are, the more a manufacturer could raise the accuracy of demand forecast, reduce the market uncertainty, and respond to the market change quickly. To sum up, the new developments of the integrated system of produciton and distribution introduced by the three companies have all had in common the shrinkage of the lot size of production planning and the reduction of leadtime for production scheduling. (2) Nevertheless, since the relative emphasis which the companies give to the improvement of this sysytem depends on the particular characteristics of their production technologies and markets, they do not share the same way of refining it. Because of longer leadtime for and larger lot size of production compared with those of the automobile company, the steel company and semiconductor manufacturer still face some difficulties in pursuing the above mentioned direction. From the results of my research I have concluded that the automobile company alone can possibly focus the improvemenmt of the sysytem in such a direction. We can see that the automobile company has established the most advanced and refined integrated system of production and distribution.
