Pickles, A. 1987. in de Zeeuw 1987, p. 203
The evidence for both metallicity and age spread within stellar composite systems (SCS) is reviewed. The role of metallicity dispersion within evolutionary syntheses and the effect of that dispersion on the calculation of age dispersion within SCS are considered. Dwarf-to-giant ratios and M/L in SCS are examined. Prospects for an expanded synthesis scheme based on available observations and theoretical data are outlined.