  The motivation and major ways for probing the Zone of Avoidance (ZOA) are
reviewed. Galaxies hidden behind the ZOA may have important implications for
the internal dynamics of the Local Group, for the origin of its motion relative
to the Microwave Background, and for the connectivity of the large scale
structure. Current direct (`observational') methods for exploring the ZOA
include eye-balling of plates, source identification in the IRAS data base and
pointed and blind-search observations in 21 cm. Interesting regions identified
so far include the two crossing points of the Supergalactic Plane by the
Galactic Plane (at Galactic longitude $l \sim 135^o$, near Perseus-Pisces, and
$l \sim 315^o$, near the Great Attractor), the Puppis cluster (at $l \sim
240^o, cz \sim 1500$ km/sec) and the Ophiuchus cluster (at $l \sim 0^o, cz \sim
8400$ km/sec). New promising wavelengths are the $2 \mu$ and the X-ray band.
Indirect (`theoretical') approaches include `Wiener reconstruction' from
incomplete and noisy data, and using the peculiar velocity field as a probe of
the mass distribution hidden behind the ZOA. The problem of source confusion at
low Galactic latitude can be addressed by novel statistical methods, e.g.
Artificial Neural Networks.
