Rolling admissions is when they select and notify applicants of their admissions (or rejection) while the admissions process is incomplete and on-going. Non-rolling admissions is when they review all applicants and, at the end of that process, select and notify their admittees and rejectees. With non-selected(ive) secondaries, anyone who indicates an interest in the school on their primary AMCAS application is invited to submit a secondary, with selected(ive, screened) secondaries, the school reviews primary applications and then invites secondaries only from a selected group.