Abstract: A screen panel retainer system is useable to retain a plurality of screen panels to a separatory machine. Retainer bars are attached to the screen stringer rails of the separatory machine by an expanding of spaced plugs that are received in holes in the stringer rails. The retainer bars each include a plurality of ears that are receivable in pockets that are situated on the inner faces of screen panel edge strips. A plurality of dams, each of which is securable to the screen edge strip ends of two adjacent screen panels, serve to further secure the screen panels in place. Screen panel removal is easily accomplished and the system is adaptable to various machine configurations.