it was predicted already more than 20 years ago that coexisting oblate-and
prolate-shaped minima should come down in energy in neutron-deficient polon
ium isotopes around Po-192. Progress in experimental techniques, and in par
ticular in the use of the Recoil-Decay-Tagging method, has made it possible
to verify these predictions. Recent RDT results obtained at the University
of Jyvaskyla on shape coexistence in very neutron-deficient Po isotopes wi
ll be discussed.