During this quarter further investigations of alternative designs for the Lincoln Training System LTS-4 project's features and subsystems continued. Software efforts proceeded concurrently in three areas: 1) system architecture, monitor, and input/output programs; 2) a new version of the Lincoln Terminal Language, LTL-2; and 3) programs to apply LTL to author needs. Hardware developments resulted in the design and installation of a new film gate in the image rotator and in the implementation of a new vernier positioning technique. In addition, most of the parts for the rotating microscope selector/reader were released for fabrication and the self-processor interface was nearly completed. Finally, considerable progress was made on the development of system software utilizing the MCS-4 simulator. (Author/PB)