  Understanding the galaxy in which we live is one of the great intellectual
challenges facing modern science. With the advent of high quality observational
data, the chemical evolution modeling of our galaxy has been the subject of
numerous studies in the last years. However, all these studies have one missing
element which is the evolution of close binaries. Reason: their evolution is
very complex and single stars only perhaps can do the job. (Un)Fortunately at
present we know that a significant fraction of the observed intermediate mass
and massive stars are members of a binary or multiple system and that certain
objects can only be formed through binary evolution. Therefore galactic studies
that do not account for close binaries may be far from realistic. We
implemented a detailed binary population in a galactic chemical evolutionary
model. Notice that this is not something simple like replacing chemical yields.
Here we discuss three topics: the effect of binaries on the evolution of 14N,
the evolution of the type Ia supernova rate and the effects on the G-dwarf
distribution, the link between the evolution of the r-process elements and
double neutron star mergers (candidates of short gamma-ray burst objects).
