Radiative Transfer in Spiral Galaxies

The internal dust extinction in spiral galaxies can affect our understanding of their structure and morphology, as well as our perception of the distant universe in the background. The intrinsic properties of the stellar and dust components can be studied by comparing the observed appearance of a dusty spiral in the optical with a radiative transfer model. The absorbed starlight is re-radiated by dust in the FIR/sub-mm. Thus, observations at long wavelengths allow to put further constraints on the properties of the dust distribution. I present our Monte Carlo simulations for dust extinction and emission in galactic disks, discuss the basic ingredients and limitations and compare them with other solutions for the radiative transfer available in the literature. I review the current picture of dusty disks that emerges from radiative transfer studies.