An important issue for optimal operation and plantwide control is to find the degrees of freedom available for optimal operation. A previously published systematic approach to determine the steady state degrees of freedom is expanded to take into account the active charge as a possible degree of freedom in cyclic processes. Additional degrees of freedom related to the composition of the circulating refrigerant are also discussed. Two liquified natural gas (LNG) processes Of Current interest, the C3MR process from Air Products and the mixed fluid cascade (MFC) process developed by Statoil-Linde LNG Technology Alliance, are studied with respect to operational degrees of freedom.