Abstract: A method of carrying out a fiber or paper manufacturing process using a plurality of successive method steps is provided. Defined process steps are carried out by means of predefinable chemical and physical sequences and process optimization is performed, wherein at least those characteristic variables of all the individual method steps which influence the target variables of the respective end product of the method in a significant way are registered on-line to control or optimize the overall process. Characteristic variables are formed both on the basis of the starting materials or raw materials and of the chemicals, auxiliaries and energy supplied in the successive method steps as well as of the materials and emissions to be disposed of.