  While ALMA and JWST are revolutionizing our view of star and planet formation
with their unprecedented sensitivity and resolution at submillimeter and
near-IR wavelengths, many outstanding questions can only be answered with
observations in the thermal (mid- and far-) infrared domain. Many of these
questions require space-based observations, to achieve the necessary
sensitivity and/or wavelength coverage. In particular, how do interstellar
clouds develop filamentary structures and dense cores? What are the masses and
luminosities of objects at the earliest stages of star formation? What are the
gas masses of planet-forming disks, and how do these disks disperse during
planet formation? How is refractory and volatile material distributed within
the disks, and how does this evolve with time? This article reviews how
upcoming and planned balloon-borne and space-based telescopes for the mid- and
far-infrared will address these questions, and outlines which further missions
will be needed beyond 2030, when the ELTs will be in full operation.
