  Dust offers a unique probe of the interstellar medium (ISM) across multiple
size, density, and temperature scales. Dust is detected in outflows of evolved
stars, star-forming molecular clouds, planet-forming disks, and even in
galaxies at the dawn of the Universe. These grains also have a profound effect
on various astrophysical phenomena from thermal balance and extinction in
galaxies to the building blocks for planets, and changes in dust grain
properties will affect all of these phenomena. A full understanding of dust in
all of its forms and stages requires a multi-disciplinary investigation of the
dust life cycle. Such an investigation can be achieved with a statistical study
of dust properties across stellar evolution, star and planet formation, and
redshift. Current and future instrumentation will enable this investigation
through fast and sensitive observations in dust continuum, polarization, and
spectroscopy from near-infrared to millimeter wavelengths.
