  A new set of evolutionary synthesis spectra are presented for {\bf S}imple
{\bf S}tellar {\bf P}opulations ({\bf SSP}s) covering ranges in metallicity
from $ 0.02 \leq Z/Z_{\odot} \leq 2.5$ and ages from $4\cdot 10^6$ yr $\leq t
\leq 16$ Gyr. They are based on the most recent isochrones from the Padova
group that extend earlier models by the inclusion of the thermal pulsing AGB
phase for stars in the mass range $2 M_{\odot} \leq m \leq 7 M_{\odot}$ in
accordance with the fuel consumption theorem. We show that with respect to
earlier models, inclusion of the TP-AGB phase leads to significant changes in
the $(V-I)$ and $(V-K)$ colors of SSPs. Using model atmosphere spectra from
Lejeune et al, we calculate the spectral evolution of single burst populations
of various metallicities. Isochrone spectra are convolved with filter response
functions to describe the time evolution of luminosities and colors in various
filter systems. The models and their results are not only intended for use in
the interpretation of star clusters but also for combination with any kind of
dynamical galaxy formation and/or evolution model that contains a star
formation criterion. We also present the time evolution of ejection rates for
gas and metals for two different {\bf I}nitial {\bf M}ass {\bf F}unctions ({\bf
IMF}s) as well as cosmological and evolutionary corrections for all the filters
as a function of redshift and two different cosmologies. Extensive data files
are provided in the electronic version, at CDS, and at our above www-address.
