  In 1985 Goode and Wainwright devised the concept of an isotropic singularity.
Since that time, numerous authors have explored the interesting consequences,
in mathematical cosmology, of assuming the existence of this type of
singularity. In this paper, we collate all examples of cosmological models
which are known to admit an isotropic singularity, and make a number of
observations regarding their general characteristics.
