The work reported here was performed between 1 June 1967 and 31 May 1968 under Task I of the contract between Chemical Abstracts Service (CAS) and the National Science Foundation (NSF). The objective of this contract was to achieve an operational, integrated, man-machine system for manipulating information about chemical substances. The contract was directed at the development of a computer-based Chemical Compound Registry System through the buildup of machine and manual files of chemical structural representations, chemical nomenclature, molecular formulas, and bibliographic citations associated with the registere d compounds. To meet this objective the contract called for the registration of compounds from several sources. Progress was made in the number of compounds registered from all sources. CAS worked to extend the range of compounds that could be machine-registered and to improve the overall efficiency and effectiveness of the system by shifting additional tasks to the computer to improve the technical and/or economic performance of the system. (RR)