The purpose of this report is to compare part-time day release and block release schemes available to apprentices and trainees in the engineering industry. (Block release provides for one or more periods of continuous attendance at college for study and workshop instruction; one session does not exceed 18 weeks.) The main focus is on educational achievement, but attitudes of apprentices toward block and day release, their college courses, and their training are also discussed. Views of members of college staffs and industrial training personnel were also obtained. The field work took place mostly between late 1962 and 1965; the period covered is approximately two academic sessions. "From the analysis of test and examination data it is evident that, at least in the sample of colleges used, the case for block release remains unproven because the apprentices on block release have been proven more able in general. It is probably safe to infer that this applies for the training situation." (EB)