[en] The evolution of various chemical abundance parameters in the solar neighborhood is discussed in terms of models that are consistent with statistical data on stellar birthrates and death rates, the paucity of metal-poor stars, and the undetectably slow increase in mean metallicity in time for disk stars. A new analytical approximation is given for treatment of stars with lifetimes between about 10⁹ years and the age of the Galaxy; although most parameters are predicted adequately by the earlier approximation of instantaneous recycling, the new method reveals systematic trends in abundances of elements made in low-mass stars.Chemical inhomogeneities in the interstellar medium are found to have extremely important effects on correlations among abundances, if the observed dispersions are due to real scatter than to errors. Most tests that would otherwise be useful for distinguishing among evolutionary models, between primary and secondary nucleosynthesis for certain elements, etc., are greatly complicated. Published data on s-process elements, carbon, and nitrogen are given tentative interpretations in terms of gaseous mixing times, stellar lifetimes, and the frequency of star formation. Accurate stellar ages would be very useful, as would dynamical and kinematic models of the Galaxy, to evaluate the effects of gas flows and motions of stars