  The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton
multi-purpose liquid scintillator detector currently being built in a dedicated
underground laboratory in Jiangmen (PR China). JUNO' s main physics goal is to
determine the neutrino mass ordering using electron anti-neutrinos from two
nuclear power plants at a baseline of about 53 km. JUNO aims for an
unprecedented energy resolution of 3% at 1 MeV for the central detector, with
which the mass ordering can be measured with 3 - 4 $\sigma$ significance within
six years of operation. Most neutrino oscillation parameters in the solar and
atmospheric sectors can also be measured with an accuracy of 1% or better.
Furthermore, being the largest liquid scintillator detector of its kind, JUNO
will monitor the neutrino sky continuously for contributing to neutrino and
multi-messenger astronomy. JUNO' s design as well as the status of its
construction will be presented, together with a short excursion into its rich
R&D program.
