The discovery of extra-solar planetary systems with properties so different from those of our own Solar System has overturned our theoretical understanding of how planets and planetary systems form. Indeed, planet formation models have to link observations of two classes of objects: Protoplanetary disk, whose structure and early evolution provide the initial conditions of planets formation, and actual detected planets. The observational knowledge of these two classes of objects will see in the near future dramatic improvements, with three major breakthroughs: 1) high angular resolution observations will tightly constrain the structure and early evolution of protoplanetary disks, 2) direct observation of extrasolar planets will allow to understand their internal structure as well as their formation process, and 3) detection of very low mass extrasolar planets will constrain the mass function of planets and planetary systems, down to the terrestrial planet regime The goal of this project is to develop a theoretical understanding of planet formation that quantitatively stands up to these observational confrontations. For this, we will build on the basis of first generation planet formation models developed at the time the PI was assistant at the Physikalisches Institute of the University of Berne. The PI, a PhD student, and a Postdoc will conduct three inter-related sub-projects linked to the three breakthroughs mentioned above: A) improving the disk part of planet formation models, B) determining the internal structure of forming planets, including the effects of accretion shocks and envelope pollution by infalling planetesimals, and calculating their early evolution, and C) building planetary system formation models, including both gas giant and low mass rocky planets.