  The JSNS$^2$ experiment aims to search for the existence of neutrino
oscillations with $\Delta {\rm m}^2$ near 1 eV$^2$ at the J-PARC Materials and
Life Science Experimental Facility (MLF). A 3~GeV 1~MW proton beam incident on
a mercury target produces an intense neutrino source from muon decay at rest
($\mu^{+} \rightarrow e^{+} + \bar{\nu}_{\mu} + \nu_{e}$). The oscillation to
be searched for is $\bar{\nu}_{\mu}$ to $\bar{\nu}_{e}$, detected via the
inverse beta decay~(IBD) reaction ($\bar{\nu}_{e} + p \rightarrow e^{+} + n$),
which is then distinctively tagged by gammas from neutron capture of
Gadolinium. The first of two detectors with 17 tons fiducial volume is
currently under construction at a distance of 24 m from the mercury target.
JSNS$^2$ is expected to provide the ultimate test of the LSND anomaly by
replicating nearly identical conditions. The status of the experiment, which is
expected to start taking data in Spring 2019, is discussed and its physics
potential reviewed.
