To establish the precise effects of using MARC II in West Sussex, and how it could assist the library staff were the goals of this feasibility study. It illustrates the development of the library catalog and associated systems as both realistic and practical. It indicates what kind of repercussions will be felt by the library and how it could improve the service to the readers. The advantages and disadvantages of the various alternative means of producing the new catalog are discussed. It is considered that the relative complexity of microfilmed catalogs, compared with the printed catalog, might well generate further adverse public comment. For this reason the feasibility study team considers the printed book version as the most satisfactory method of producing the catalog. The use of disc storage facilities is expected to reduce annual operational costs. Initial development and conversion costs are estimated on the basis of the existing installation at County Hall, though future hardware provision may necessitate some modification. At the current rate of growth, under normal conditions, the size of the catalog is expected to increase by approximately 5-10% per annum. This is not likely to cause insurmountable processing problems. (Author/CH)