An upper guide track assembly for a retractable screen is described. The assembly comprises a U shaped guide channel, a track attachment member for attaching the assembly to a support, a track outer member connectable to the attachment member and a screen retaining member within the guide channel. The retaining member receives and retains an upper edge of a screen. The retaining member has two resilient wings extending from either side of the body. Each wing is biased towards a position in which the distal end of each wing is away from the body. The wings are moveable against the bias to a retracted position. When the retaining member is retained in the guide channel, each wing is held in the retracted position against the bias. This allows an upper edge of a screen retained by the screen retaining member to be biased in the vertical direction.