A method and system for generating trusted security labels in electronic documents is disclosed. The method comprises determining parts of the document to be cryptographically bound to the security label and hashing them; hashing the security label; specifying any necessary policies as signable signature properties; and digitally signing the collection of these items. The resulting security label is trusted, because it is digitally signed and its digital signature also covers the parts of the document to be protected, thus allowing any tampering of the security label or the covered parts of the document to be detectable. A corresponding system for generating trusted security labels is also provided.