With the observation of the first gravitational-wave event from a binary neutron star, GW170817, during Advanced LIGO and Virgo's second observation run, multimessenger astronomy with gravitational waves has started. The current generation of gravitational-wave detectors now serves a wide community including fundamental physics, astrophysics, astronomy, cosmology and nuclear physics. The observations to date and their widespread impact on science make the argument for future facilities quite compelling.
The two-day program of this workshop will focus on global strategies for third-generation (3G) gravitational-wave observatories and detectors, and their science case. Of particular interest is the proper coordination between the European effort proposing to build an observatory detailed by the 'Einstein Telescope' design study, and the U.S. proposal of a similar class observatory, named 'Cosmic Explorer'.