A Tiltable and slidable roof panel assembly for a motor vehicle comprises a roof panel (3) supported by a front support (4) and a rearward lifters (5) on a respective guide rail (6) extending along a side of an aperture (2) in the vehicle roof (1) and rearwardly beyond the aperture of the fixed roof. The lifter (5) is adapted to be driven by a driver means (8), on the one hand in a sliding movement along the guide rail (6) in order to slide the panel (3), and on the other hand in an up and down movement to enable the panel (3) to move between its closed position and an upwardly displaced venting position and between its closed position and a downwardly displaced position prior to the sliding movement of the panel. The lifter (5) includes a set-out lever (9) being at least pivotally in engagement with the panel through a first pivot (13) on the one hand and being pivotally and slidably connected with the guide rail ( 6) by a second pivot (11) on the other hand. An auxiliary lever (10) is in engagement with the set-out lever (9) spaced from the second pivot (11) during the pivoting movement of the panel. The movements of the set-out lever (9) are controlled by a forcing guide (10, 17, 23, 18, 24). The set-out lever (9) and the auxiliary lever (10) are guided during the pivoting movement of the panel (3) such that they both pivot and slide with respect to each other, whereby during the relative sliding movement between the set-out lever (9) and the auxiliary lever (10) one of these is substantially prevented from sliding relative to the guide rail (6) by means of a locking stop (30,31,20,33).