  I review recent advances in the determination of the cosmic history of star
formation, and its relevance in our understanding of the formation of
structures. I emphasize the importance of dust reprocessing in the high--z
universe, as demonstrated in particular by IR and sub-mm data. This demand a
panchromatic approach to observations and suitable modelling tools. I summarize
the basic requirements for these models and to what extent they are satisfied
by models published so far.
