A method of identifying a caller with a telephone service operator. Of the invention, said method comprises the following steps: for the operator, drawing up a list of literal expressions and allocating the caller an identifier consisting of a combination of consecutive literal expressions taken from each of said lists, for the caller, connecting to said telephone service and speaking, in order, each literal expression of said combination, and for the operator, identifying the caller by using voice recognition to search for the combination of literal expressions allocated to the caller. Application to secure access to telephone services.