  Results of a large program of spectroscopic monitoring of nearby solar-type
stellar hierarchical systems using the CHIRON echelle spectrograph at the 1.5 m
telescope are summarized. Ten papers of this series contain 102 spectroscopic
orbits and substantially contribute to the knowledge of periods and
eccentricties, providing input for the study of their formation and early
evolution. Radial velocities of additional 91 targets without CHIRON orbits
(members of wide physical pairs) are published here. Our results are compared
to the recent Gaia Non-Single Star (NSS) catalog, revealing its strengths and
weaknesses. The NSS provides orbital periods for 31 objects of the CHIRON
sample (about one third). Of the 22 spectroscopic NSS orbits in common, 14 are
in good agreement with CHIRON, the rest have reduced velocity amplitudes or
other problems. Hence ground-based monitoring gives, so far, a more accurate
and complete picture of nearby hierarchies than Gaia. The distribution of inner
periods in hierarchical systems is non-monotonic, showing a shallow minimum in
the 30-100 days bin and a strong excess at shorter periods, compared to the
smooth distribution of simple binaries in the field. The period-eccentricity
diagram of inner subsystems updated by this survey, recent literature, and
Gaia, displays an interesting structure.
