Touring the stages of star and planet formation

While the stages in the formation of stellar systems are now well charted, uncertainties in the initial conditions and evolution lead to stellar systems with a diverse array of architectures.  In this talk I will discuss the major stages in the evolution of young stellar objects, starting from the young protostars and ending in stars that have dispersed all circumstellar material.  At each step I will describe insights into some of the relevant processes that are being obtained from ongoing observational programs.  For protostars, we are pursuing the first long-term monitoring program in the sub-mm to establish the role of accretion variability during the main phase of stellar growth.  The next stage, protoplanetary disks, is now being revolutionized by exquisite ALMA images of substructures, which point to the presence of hidden planets. Gaia observations of young stars that have shed their disk promise to reveal the recent star formation in our local neighborhood, although this will require improved measurements of stellar properties.  Finally, at the end I will discuss ongoing and future efforts that will shed light on star and disk formation, including with the HST/ULLYSES program, JWST, and eventually the TMT.