This thesis aims to study low-energy strong interaction effects of open-charm mesons. Our studies are based on the chiral Lagrangian supplemented by constraints from the heavy-quark spin symmetry. The pseudoscalar and vector open-charm-meson masses are calculated up to next-to-next-to-next leading order (N^3LO) corrections. Different assumptions on the counting rules are investigated. It is illustrated that a chiral expansion uniformly converges rapidly up to Goldstone boson masses as heavy as the kaon masses if formulated in terms of physical meson masses. First estimates of the relevant low-energy parameters are extracted from lattice QCD data on the quark mass dependence of the D meson masses. Such low-energy parameters are of crucial importance for the low-energy interaction of the Goldstone bosons with the D mesons.