The basic physics of quantum-correlated $D^0, \bar{D}^0$
pairs produced at threshold via decays of the $\psi(3770)$
is introduced. The connection to extractions of the CKM
angle $\gamma(\phi_3)$ from $B$ decays is emphasized
throughout. Recent quantum correlation results from BESIII
and CLEO-c are then summarized before closing with a
discussion of selected issues.