  We demonstrate the possibility of forming a single, large domain of
disoriented chiral condensate (DCC) in a heavy-ion collision. In our scenario,
rapid initial heating of the parton system provides a driving force for the
chiral field, moving it away from the true vacuum and forcing it to go to the
opposite point on the vacuum manifold. This converts the entire hot region into
a single DCC domain. Subsequent rolling down of the chiral field to its true
vacuum will then lead to emission of a large number of (approximately) coherent
pions. The requirement of suppression of thermal fluctuations to maintain the
(approximate) coherence of such a large DCC domain, favors three dimensional
expansion of the plasma over the longitudinal expansion even at very early
stages of evolution. This also constrains the maximum temperature of the system
to lie within a window. We roughly estimate this window to be about 200 - 400
MeV. These results lead us to predict that extremely high energy collisions of
{\it very small nuclei} (possibly hadrons) are better suited for observing
signatures of a large DCC. Another possibility is to focus on {\it peripheral}
collisions of heavy nuclei.
