[en] The clan description of multiparticle production process suggested by Giovannini and Van Hove is discussed on the base of quantum master equations for open systems. It is shown that the Poisson distribution of fragments created on the first hard stage is model independent to a great extent and can be obtained from rather general assertions of the theory of open systems. The second stage or development of the avalanche is characterized by self-organizing critical behaviour. The stage of hadronization can be satisfactorily described with the help of the model of two-level sources and reminds of the laser operation under the coherent threshold. A possible cause of deviation of multiplicity distributions from the NB regularity and the hypothesis of local parton-hadron duality is also discussed. 27 refs