  The CALET Gamma-ray Burst Monitor (CGBM) is the secondary scientific
instrument of the CALET mission on the International Space Station (ISS), which
is scheduled for launch by H-IIB/HTV in 2014. The CGBM provides a broadband
energy coverage from 7 keV to 20 MeV, and simultaneous observations with the
primary instrument Calorimeter (CAL) in the GeV - TeV gamma-ray range and
Advanced Star Camera (ASC) in the optical for gamma-ray bursts (GRBs) and other
X-gamma-ray transients. The CGBM consists of two kinds of scintillators: two
LaBr$_3$(Ce) (7 keV - 1 MeV) and one BGO (100 keV - 20 MeV) each read by a
single photomultiplier. The LaBr$_3$(Ce) crystal, used in space for the first
time here for celestial gamma-ray observations, enables GRB observations over a
broad energy range from low energy X-ray emissions to gamma rays. The detector
performance and structures have been verified using the bread-board model (BBM)
via vibration and thermal vacuum tests. The CALET is currently in the
development phase of the proto-flight model (PFM) and the pre-flight
calibration of the CGBM is planned for August 2013. In this paper, we report on
the current status and expected performance of CALET for GRB observations.
