Heavy quarks and QCD matter

I present recent results on the theory of QCD matter production in high energy heavy ion collisions and on the interactions of heavy quarks in such environment. The centrality and rapidity dependence of hadron production is evaluated in semi-classical approach. The energy loss of heavy quarks in matter is computed. The heavy-to-light meson ratio (e.g., D/π) at moderate transverse momenta is demonstrated to be both sensitive to the density of color charges in the medium and infrared stable.