The article deals with the issue of so-called true and false concentration in administrative proceedings, which can be understood as an exception to the principle of unity of proceedings, valid as the main principle governing administrative proceedings. In addition to the administrative code, the so-called centralization principle is also enshrined in special laws. While the true concentration is not challenged to use the false concentration, both the jurisprudence and the doctrine are restrictive or even dismissive. The possibility of concentration is significantly limited for appeal proceedings.