A seat cushion adjustment device depends on an adjustment path of at least one main adjustment of the seat and serves to define a development curve of the seat cushion adjustment individually and ergonomically. The seat cushion adjustment device includes a first adjustment device for a main adjustment of the vehicle seat within a defined adjustment area and a second adjustment device coupled to the first adjustment device for adjusting the seat cushion in dependence on a main adjustment of the seat cushion in dependence on a main adjustment of the vehicle seat. The seat cushion adjustment device also includes a separate adjustment device coupled to said first or second adjustment device for fixing the development curve of the seat cushion adjustment device within a restricted adjustment area, whereby the extreme positions of the seat cushion are associated with the extreme positions of at least one main adjustment of the vehicle seat.