A polymer expansion is given for the Quantum Heisenberg Ferromagnet wave
function. Working on a finite lattice, one is dealing entirely with algebraic
identities; there is no question of convergence. The conjecture to be pursued
in further work is that effects of large polymers are small. This is relevant
to the question of the utility of the expansion and its possible extension to
the infinite volume. In themselves the constructions of the present paper are
neat and elegant and have surprising simplicity.