  We consider all theories with eight supersymmetries whose reduction to three
dimensions gives rise to scalars that parametrise symmetric manifolds. We
conjecture that these theories are non-linear realisations of very-extended
Kac-Moody algebras for suitable choices of real forms. We show for the most
interesting cases that the bosonic sector of the supersymmetric theory is
precisely reproduced by the corresponding non-linear realisation.
