The very complex interplay between dust and stellar emission is reflected by the diversity of configurations: the contrast is striking between organized grand design spirals with regular distributions of each component and Submillimeter Galaxies (SMG) observed with HST and ALMA, and exhibiting a clear spatial disconnection between both stellar and dust emissions. Studying this interplay takes several ways: from radiative transfer modelling and more phenomenological approaches based on SED fitting and effective attenuation laws. The former put the physical framework, the latter capture the diversity of the configurations. I will describe how these methods work  and some of their main results, based on either observations or simulations, and underlining their complementarity. I will highlight the now widely accepted result of the non universality of the attenuation law of star forming galaxies and the implication on the measure of fundamental properties such as star formation rate or stellar mass.