A method for personalising documents, wherein each of the documents has an integrated electronic circuit, said method comprising the following steps: - receiving input data for the personalisation of the documents by a computer system of a high-security environment, - generating a key pair consisting of a public key and a private key for each of the documents, wherein the key pair is generated by a cryptographic unit of the high-security environment, - instantiating a predefined data structure consisting of the input data and one of the public keys for each of the documents by the computer system, - generating a digital signature of the instantiated data structure by the cryptographic unit, - generating control data for personalising the documents in each case with one of the instantiated and signed data structures and the private key assigned to the specific instantiated data structure in question by the computer system, - transferring the control data from the computer system to a personalisation device of a production environment, - transferring the instantiated and signed data structures and the corresponding assigned private keys from the personalisation device to the documents in accordance with the control data, - storing each of the data structures in a memory region of the integrated electronic circuit after verifying the signatures of the data structures, wherein the storage is performed under an access condition, - storing the private key assigned to the particular data structure in a memory region of the integrated electronic circuit, wherein the storage is performed so that no external access to the private key is possible, wherein an end-to-end encryption method is used between the cryptographic unit and the integrated electronic circuits of the documents in order to protect the transfer of the private key in question, wherein a symmetric key is stored in the cryptographic unit, and wherein the private key is encrypted with the aid of the symmetric key by the cryptographic unit such that only the encrypted private key is transferred to the computer system, and wherein the same symmetric key is stored in the integrated circuits in order to decrypt the corresponding private key prior to the storage thereof. - receiving input data for the personalisation of the documents by a computer system of a high-security environment, - generating a key pair consisting of a public key and a private key for each of the documents, wherein the key pair is generated by a cryptographic unit of the high-security environment, - instantiating a predefined data structure consisting of the input data and one of the public keys for each of the documents by the computer system, - generating a digital signature of the instantiated data structure by the cryptographic unit, - generating control data for personalising the documents in each case with one of the instantiated and signed data structures and the private key assigned to the specific instantiated data structure in question by the computer system, - transferring the control data from the computer system to a personalisation device of a production environment, - transferring the instantiated and signed data structures and the corresponding assigned private keys from the personalisation device to the documents in accordance with the control data, - storing each of the data structures in a memory region of the integrated electronic circuit after verifying the signatures of the data structures, wherein the storage is performed under an access condition, - storing the private key assigned to the particular data structure in a memory region of the integrated electronic circuit, wherein the storage is performed so that no external access to the private key is possible,