  We review basic phenomenology on $D^0$ mixing/CP violation and recent
experimental results on them. $D^0$ mixing is established by combining results
from multiple experiments but no CP violation in the charm sector has been
seen. $D^0$ mixing from a single experiment will clarify the size of the
mixing, and observation of CP violation in charm decays at the present level of
experimental sensitivity would be clear signal of new physics beyond the
standard model.
