  Over the past decade the multi-messenger astrophysics has emerged as a
distinct discipline, providing unique insights into the properties of
high-energy phenomena in the Universe. The Pierre Auger Observatory, located in
Malarg\"ue, Argentina, is the world's largest cosmic ray detector sensitive to
photons, neutrinos, and hadrons at ultra-high energies. Using its data,
stringent limits on photon and neutrino fluxes at EeV energies have been
obtained. The collaboration uses the excellent angular resolution and the
neutrino identification capabilities of the Observatory for follow-up studies
of events detected in gravitational waves or other messengers, through
cooperation with global multi-messenger networks. We present a science
motivation together with an overview of the multi-messenger capabilities and
results of the Pierre Auger Observatory.
