Standard thermodynamic parameters DeltaG, DeltaH and DeltaS for several series of coordination reactions between mixed ligand complexes of Cd(II) and single entering groups in aqueous solution at T = 298.15 K and constant ionic strength mu = 1 for KNO3 were inspected for the occurrence of enthalpy-entropy and free energy relationships. Both the series of reactions between constant substratum and variable ligands (Sub + L-(i) = Sub-L-(i): i = variable) and the series of reactions between variable Cd(II) complex substrata and constant entering ligand (Sub((i)) + L = Sub((i))-L: i = variable) disclose linear compensative DeltaH-DeltaS interplay (DeltaH = DeltaH(res) + tauDeltaS). The parameters (DeltaH(res) and tau) of the linear relationships do not discriminate within the coordination levels of the reacting substrata. The series Sub((i)) + S2O32- = Sub((i)) - S2O32- is distinguished from the other series for a more a favourable DeltaH(res). The series of reactions Sub((i)) + L = Sub((i))-L (i = variable) shows a non-linear dependence of the substratum-to-ligand affinities on the overall thermodynamic stability of the reacting substrata, The exponential relationship Y = A + B exp(CX) is proposed for describing the dependencies. The general interpretation of the parameters A, B and C are given.