Abstract: An exhaust gas turbocharger comprising a turbine with a guide apparatus comprising a ring of guide vanes arranged concentrically around a rotor axis and pivotable between two end limits. A first securing ring is arranged at the side of a bearing housing for mounting a first trunnion of each guide vane which is also mounted at the side of an oppositely disposed turbine housing. An adjusting mechanism is provided for adjusting one of the two end limits, and the guide vanes are freely pivotable under the influence of flow forces in the resulting predetemined angle adjustment range. The arrangement makes possible a compact construction which can be fabricated at reduced cost and easily assembled. This is achieved by an assembly containing the guide apparatus and the adjusting mechanism, and which includes a second securing ring arranged at the side of a turbine housing for mounting a second trunnion of each guide vane.