Abstract: A method serves for customizing the operation of a telephonic terminal, in particular a mobile telephonic terminal of a user. A profile file is provided for storing information relating to operation parameters of the telephonic terminal. The information stored in the profile file can be modifiable by the user. Additionally, a policy file is provided for storing information relating to the possibility to modify one or more of the operation parameters by the user. Typically, a profile manager software module manages the profile file and a policy manager software module manages the policy file. When a user attempts to carry out modifications on information stored in the profile file, the profile managing module interacts with the policy managing module in order to check the possibility to carry out the modifications and to get the authorisation or the denial from the policy managing module.