  We present results of a spectroscopic study of 37 southern (candidate) gamma
Doradus stars based on echelle spectra. The observed spectra were
cross-correlated with the standard template spectrum of an F0-type star for an
easier detection of binary and intrinsic variations. We identified 15 objects
as spectroscopic binaries, including 7 new ones, and another 3 objects are
binary suspects. At least 12 objects show composite spectra. We could determine
the orbital parameters for 9 binaries, of which 4 turn out to be ellipsoidal
variables. For 6 binaries, we estimated the expected time-base of the orbital
variations. Clear profile variations are observed for 17 objects, pointing
towards stellar pulsation. For 8 of them, we have evidence that the main
spectroscopic and photometric periods coincide. Our results, in combination
with prior knowledge from the literature, lead to the classification of 10
objects as new bona-fide gamma Doradus stars, 1 object as new bona-fide delta
Scuti star, and 8 objects as constant stars. Finally, we determined the
projected rotational velocity with two independent methods. The resulting vsini
values range from 3 to 135 km/s. For the bona-fide gamma Doradus stars, the
majority has vsini below 60 km/s.
