A self-controlled concentrator for packet-synchronous for fast data packet switching networks has the first bits of the totality of input data packets act on the totality of the switch elements of the concentrator in accordance with the switch positions thereof. The switch elements are beta elements (.beta.), having two inputs and two outputs, whereby 1d n stages of n/2 beta elements (.beta.) each are provided in which n is the number of inputs and outputs of the concentrator. A connecting structure that represents a perfect shuffle is provided between the stages of beta elements. The stages are divided into blocks such that the plurality of blocks increases according to a power of 2, ascending from stage to stage, whereby the plurality of blocks in the first stage is 2.sup.0, that in the second stage is 2.sup.1, etc., whereby n/2 blocks form the last stage to produce a binary tree structure. Dependent on the type of signal pair supplied to it, a beta element (.beta.) acts on a neighboring bete element to control the switch position thereof such that a concentration of the bits having a prescribed binary value at the outputs of the concentrator is produced at the last stage of the concentrator to produce a concentration of the data packets.