In this first in a series of three papers, a formal treatment is presented for the development of property correlations for homologous series of compounds. The theoretical basis for asymptotic behavior is discussed, and the methodology used to regress parameters is described. The equations developed are quite general and can be extended to other properties or homologous series. Parts 2 and 3 of this series present correlations developed for n-paraffins and n-olefins (1-alkenes) to predict PVT related properties, normal boiling and melting points, critical temperature, pressure, and volume, acentric factor, liquid molar volume, and vapor pressure (part 2); thermal properties, ideal-gas enthalpy and free energy of formation, ideal-gas heat capacity, enthalpy of vaporization, and liquid heat capacity (part 3); transport properties : liquid viscosity, thermal conductivity, and surface tension (part 3). It is demonstrated that these correlations are accurate, consistent, and yield reasonable extrapolations. They are preferable to existing correlations in most instances.