A seat 100 moveable between a seat configuration and a bed configuration, the seat 100 comprising a squab 120 including upper and lower cushions 126, 124, a conversion mechanism configured to move the squab 120, for converting the seat 100 between the seat and bed configurations, and a backrest 122 connected to the squab 120 or conversion mechanism, for moving with the squab 120, the squab 120 being laterally displaceable by the conversion mechanism between a first position in the seat configuration and a second position in the bed configuration, and the backrest 122 being configured to occupy a space at an end of the squab 120 which is made available by lateral displacement of the squab 120 into the second position, and the upper cushion 126 of the squab 120 being movable relative to the lower cushion 124 for covering the backrest 122 in the bed configuration.