Abstract: A method for operating a particle trap, in particular an open particle trap, in an exhaust gas system of an internal combustion engine, includes determining a first point in time in which the particle trap falls below a first effectiveness limiting value, increasing the effectiveness of the particle trap by adjusting at least one specific operating parameter of the internal combustion engine, while exhaust gas produced by the internal combustion engine does not exceed a temperature of 500° C. in the vicinity of the particle trap, determining a second point in time in which the particle trap exceeds a second effectiveness limiting value, and activating normal operation of the internal combustion engine. The method and an associated device ensure operation of an exhaust gas system of an internal combustion engine, with conservation of fuel, savings of materials and simultaneous high effectiveness of the particle trap integrated into the exhaust gas system.