Method for improved identification and/or authentication of a user within the context of a telephone connection or a voice call of the user with a voice telephony system, wherein, in relation to a plurality of users, in each case at least one speaker feature information item (231, 232, 233, 234) is present or is accessible together with in each case at least one caller ID information item (221, 222, 223, 224), wherein the method comprises the steps of: - in a first step, starting from a specific telecommunication terminal of a specific user, a telephone connection or a voice call to the voice telephony system is established, wherein the specific telecommunication terminal or the connection thereof is allocated a specific caller ID information item and wherein the specific caller ID information item is transmitted as the telephone connection or the voice call to the voice telephony system is being established, - in a second step subsequent to the first step, a check is made as to whether, in relation to the specific caller ID information item, at least one specific speaker feature information item is present or is accessible, - in a third step subsequent to the second step - if the check as to whether, in relation to the specific caller ID information item, a specific speaker feature information item is present or is accessible, has a positive result - a check is made as to whether a voice information item of the user which is acquired during the duration of the telephone connection or the voice call, has or produces sufficient correspondence with the specific speaker feature information item, wherein automated identification and/or authentication of the specific user is effected if such sufficient correspondence is confirmed, characterised in that, in a fourth step subsequent to the second step - if the check as to whether, in relation to the specific caller ID information item, a specific speaker feature information item is present or is accessible, has a negative result - identification and/or authentication of the specific user requires the transmission of further identification and/or authentication information, wherein, in a fifth step subsequent to the fourth step - if the check as to whether, in relation to the specific caller ID information item, a specific speaker feature information item is present or is accessible, has a negative result and after identification and/or authentication of the specific user - a check is made as to whether, in relation to the specific user, a speaker feature information item is present or is accessible, wherein, if in relation to the specific user, a speaker feature information item is present or is accessible, this speaker feature information item is allocated to the specific caller ID information item in addition to a further caller ID information item. - in a first step, starting from a specific telecommunication terminal of a specific user, a telephone connection or a voice call to the voice telephony system is established, wherein the specific telecommunication terminal or the connection thereof is allocated a specific caller ID information item and wherein the specific caller ID information item is transmitted as the telephone connection or the voice call to the voice telephony system is being established, - in a second step subsequent to the first step, a check is made as to whether, in relation to the specific caller ID information item, at least one specific speaker feature information item is present or is accessible, - in a third step subsequent to the second step - if the check as to whether, in relation to the specific caller ID information item, a specific speaker feature information item is present or is accessible, has a positive result - a check is made as to whether a voice information item of the user which is acquired during the duration of the telephone connection or the voice call, has or produces sufficient correspondence with the specific speaker feature information item, wherein automated identification and/or authentication of the specific user is effected if such sufficient correspondence is confirmed, characterised in that, in a fourth step subsequent to the second step - if the check as to whether, in relation to the specific caller ID information item, a specific speaker feature information item is present or is accessible, has a negative result - identification and/or authentication of the specific user requires the transmission of further identification and/or authentication information,