A modeling system and process for computer-aided, block-based modeling by preparing a first block diagram in a first model plane that relates to a first abstraction stage, in which at least one block is placeable in the first model plane and several blocks are connectable to one another by horizontal data transfer devices for horizontally exchanging data. At least one other block diagram is arrangeable on at least one other model plane assigned to the first abstraction stage that is separated from the first model plane. The first block diagram of the first model plane and the other block diagram of the other model plane form an overall block diagram that can be arranged on a selection of at least two model planes from the first model plane and the other model planes, so that a vertical exchange of data between at least two selected model planes can be produced.