  We review the evidence for buried ice in the asteroid belt; specifically the
questions around the so-called Main Belt Comets (MBCs). We summarise the
evidence for water throughout the Solar System, and describe the various
methods for detecting it, including remote sensing from ultraviolet to radio
wavelengths. We review progress in the first decade of study of MBCs, including
observations, modelling of ice survival, and discussion on their origins. We
then look at which methods will likely be most effective for further progress,
including the key challenge of direct detection of (escaping) water in these
bodies.
