A method for the separate authentication of a template and of data inserted therein. A template is provided with a template ID and a template Data Authentication Code (DAC(t)). User data is inserted in the template, and then extracted to be handled separately. A DAC(d) is generated on the user data by itself, and stored in an Approval Data packet with the template ID, DAC(t) and the user data. The complete document with the template and the user data can later be reconstructed. The method may be useful for many industries that rely on templates for collecting data.