A window stay, comprising: a frame plate; at least one arm coupled to the frame plate by a frame plate pivot; and a bearing plate engaged with the frame plate, the bearing plate and the frame plate together configured to be mounted to a window frame; wherein the bearing plate comprises a reinforcing insert for spreading a load applied through at least part of the at least one arm to the bearing plate; wherein the reinforcing insert is made of a material with more strength and/or rigidity than the material of the bearing plate. A window stay comprising: a frame plate; at least one arm coupled to the frame plate by a frame plate pivot; and a bearing plate engaged with the frame plate, the bearing plate and the frame plate together configured to be mounted to a window frame having a frame channel; wherein the bearing plate comprises a support member for supporting the bearing plate above the frame channel; wherein the support member is a projection that extends from beneath the bearing plate.