m_u + m_d from QCD-Hadron Duality

The value of the light quark masses combination $m_u+m_d$ is analized using QCD-Hadron Duality. A detailed analysis of both the perturbative QCD [to four-loops] and the hadronic parametrization needed is done. The result we get is $[m_u+m_d](1Ge{V}^2)=(12.8\pm 2.5)$ MeV ($[m_u + m_d] (4 GeV^2) = (9.8 \pm 1.9)$MeV)inthe$\barMS$ scheme.