Abstract: In an exhaust gas turbocharger for an internal combustion engine, in which a compressor is disposed in the intake duct and a turbine is disposed in the exhaust duct, and wherein the turbine has a turbine wheel in a turbine housing with at least one inlet flow passage for the introduction of exhaust gas which flow passage is provided with a variable turbine geometry for the variable setting of the effective turbine inlet flow passage cross-section, the variable turbine geometry being adjustable between a shut-off position that minimizes the turbine inlet flow cross-section and an open position that maximizes the turbine inlet flow cross-section, a gas-collecting chamber is provided which is in communication with the inlet flow passage in the turbine housing, the total volume of flow passage and the gas-collecting chamber being adjustable by an actuator movably disposed in the turbine housing as a function of the operating state of the internal combustion engine.