This paper is the second step in the preparation of forecasts of occupational and industrial information which will meet the needs of the Information System for Vocational Decisions (ISVD). The author discusses the computation routines which need to be developed, tested and operationalized toward the goal of combining occupational and industrial information and projections, and storing, processing and retrieving it. The paper begins with a fairly abstract discussion of the terminology and principles to be used. These principles are then applied to the collection of information from the available sources. (TL)