A smoke or fire barrier for a pedestrian way, having two sides (4,5) and a head, the barrier comprising: • a curtain support normally arranged at the head of the pedestrian way; • a curtain (17,117,317) normally supported by the curtain support for deployment down between the sides of the pedestrian way in event of smoke or fire; and • two movable side guides (14,15,114,115,314) for the curtain, wherein either: • one of the movable side guides (14,114) is hinged to its side of the pedestrian way and the other movable side guide (15,115) is able move away from its side throughout its height; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being slideable sideways in the manner of a sliding door; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being centrally pivoted; • so that at least partial, temporary opening of the barrier is provided to allow escape of an evacuee needing to use the pedestrian way after deployment of the barrier. • a curtain support normally arranged at the head of the pedestrian way; • a curtain (17,117,317) normally supported by the curtain support for deployment down between the sides of the pedestrian way in event of smoke or fire; and • two movable side guides (14,15,114,115,314) for the curtain, wherein either: • one of the movable side guides (14,114) is hinged to its side of the pedestrian way and the other movable side guide (15,115) is able move away from its side throughout its height; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being slideable sideways in the manner of a sliding door; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being centrally pivoted; • so that at least partial, temporary opening of the barrier is provided to allow escape of an evacuee needing to use the pedestrian way after deployment of the barrier. • one of the movable side guides (14,114) is hinged to its side of the pedestrian way and the other movable side guide (15,115) is able move away from its side throughout its height; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being slideable sideways in the manner of a sliding door; or • the two movable side guides are able to move away from their sides and are connected by a top member uniting the guides and containing the curtain support, the side guides and the top member and curtain support being centrally pivoted; • so that at least partial, temporary opening of the barrier is provided to allow escape of an evacuee needing to use the pedestrian way after deployment of the barrier.