A system for use in a lithographic apparatus comprises: a substrate table; another device; and at least one deformable partition. The substrate table (for example a wafer stage) is arranged to support a substrate. The system is configurable in a first configuration such that a surface of the device faces and is adjacent to the substrate and the substrate table. The at least one deformable partition either: (a) extends partially from the substrate table towards the surface of the device when the system is in the first configuration; or (b) extends partially from the surface of the device that faces and is adjacent to the substrate and the substrate table when the system is in the first configuration towards the substrate table.