Recent IRAM interferometric results have started to unveil some of the detailed physics at work in proto-planetary disks: evidence for dust size radial segregation, and disks preading with time, perhaps of dust settling, but also more intricate measurements like a direct measure of turbulence and the detection of cavities which may trace planetary formation.

 A few more molecules have been also discovered recently, but the molecular complexity in disks still appears quite limited.

 Combining these results with lessons learned from a recent survey for molecules in disks at the 30-m, I will show how ALMA can help us to improve our knowledge of the physics of disks.