All raw meat Preclears (one who has never had Scientology processing), before being run on Level Zero, should be run on ARC S/W, Secondaries and ENGRAMS. This, then, gets their basic levels in.

On the Dianetic Courses running ARC S/W, Secondaries and ENGRAMS comes as the last requirement after the Course Supervisor is satisfied that the TRs 0 to 4 are in on the Student.