Cool Stars 14 - Submitted Abstract # 311 This version created on 05 October 2006 Dust evolution and planet formation in disks around young stars Nuria Calvet, University of Michigan, Ann Arbor Recent Spitzer observations of protoplanetary disks in the Taurus-Auriga cloud show evidence of significant dust evolution. I will review these observations and their interpretation. I will also describe the transition disks, a particularly interesting disk evolutionary stage in which planets may already have formed. ----------------------------------