  Recent theoretical and experimental improvements in the determination of
charm and bottom quark masses are discussed. The final results, $m_c(3
\text{GeV})=986(13) $MeV and $m_b(m_b)=4163(16) $MeV represent, together with a
closely related lattice determination $m_c(3 {\rm GeV})=986(10) $MeV, the
presently most precise determinations of these two fundamental Standard Model
parameters. A critical analysis of the theoretical and experimental
uncertainties is presented.
