At the beginning of the last century the kinetic theory for single-sited enzyme system was formulated and the technique of their full kinetic analysis was refined. Its essence consisted in the transformation of hyperbolic function into a rectilinear dependency, that is characteristic of only single-sited systems. Later on, however, it was found that many enzymes because of their multi-site feature are characterized by curve-linear kinetic dependency. This necessitated to formulate principles for kinetic analysis of such curves and to work out new kinetic parameters. In spite of multiple attempts made in this direction this goal has not been achieved. The monograph is concerned with theoretical basis for deciphering the molecular mechanism for the multi-sited enzyme systems, and relying on experimental data, statistically valid methods for the determination of fundamental kinetic parameters is set forth.