The SU3 model of Elliott provides the basic elements that make it possible
to understand the collective relations of nuclei in a spherical shell-model
framework. Recent experimental results in medium mass nuclei have delineat
ed new regions of deformation, in places where very large shell-model calcu
lations are now feasible. It turns out that many features of these deformed
nuclei can also be understood within an approximate version of SU3.