This paper describes a new model updating approach based on the standard sensitivity method combined with a new method for automatic selection of updating parameters. It is no longer necessary to select specific updating parameters and to proceed with a global optimisation using these selected parameters. The new method for automatic selection allows the analyst to select any number of updating parameters. The method is based on an assessment of the contribution for each updating parameter to the rank of the sensitivity matrix, and the final selection of updating parameters is performed iteratively by removing the updating parameters which contribute least so long as the rank of the sensitivity matrix is outside a specified value. This solution procedure is performed at every iteration during updating and this ensures that the sensitivity matrix is well conditioned throughout the whole updating process. The technique can be applied to both the modal- and response-based updating approaches. The application of the method is demonstrated on a number of real engineering structures rather than using simulated experimental data.